Quicksilver PSU Fan Replacement

Most PowerMac G4s are about 20 years old now, which means they all need some degree of work to run as well as they did when they were new. Fans are one of the most common replacements needed, and in most G4s, the fan in the power supply is the first to go. This post exists to serve as a basic guide for how to replace that fan. In the case of my Quicksilver, it is a standard 80mm x 80mm x 25mm PC fan. I used a part pulled from a few-years-old office PC. It's worth noting that the it only needs power and ground, PWM and sense lines on most modern fans are not connected at all. In my case, I cut them off.

To start, power off the machine and open it. I removed the HDD carriers to give a bit more space.

one

Remove the optical drive carrier. There are four screws, two at the top, one underneath, and one on the front panel. These screws are the same. It will take some wiggling to get it to come out, and expect the power cables to be VERY stiff if they haven't been removed before.

two

Now remove the bracket behind the PSU. Three screws, two behind the PSU and one under it. The bracket will pop straight out. After that, remove the big 120mm fan (don't forget to disconnect its power source!) There are two large screws with big flat heads holding it in, one is holding down a black plastic cable wrap, the other is under the fan. The fan will kind of drop out once this is done.

Next comes the rear PSU screws. These are three 2.5mm hex screws. Once removed, the PSU can be slid backwards and then tipped into the case. Once tipped into the case, feed the power cables up through the opening in the horizontal bracket.

With the chassis being nice and empty, this is a good opportunity to clean out any dust that may have accumulated.

Now that the PSU is out, we can disassemble it and replace the fan. Taking it apart is very easy - four screws right on top, then the top metal case will lift straight off. All standard precautions regarding working in AC voltage equipment apply. If you want to be extra safe, wait a day with the PSU completely disconnected to allow the capacitors to discharge completely.

PSU fan area

In this picture you can see that I've already pulled out the fan, and I've also cut out the metal grille at the back of the power supply - more on that in a moment. Removing the fan is trivial. Unscrew the two screws at the rear holding it in, move the blue and brown AC cables routed above it (you may need to snip a cable tie and pop the ferrite bead off of the fan), disconnect the fan's power connector, then push the rear of the metal PSU casing outwards in order to slide the old fan up and out. This is also a good opportunity to clean up the dust that has accumulated within the PSU.

If your new fan has a similar type of connector, swapping the old one should be easy. Use a small pin or screwdriver to push down the locking tabs on the metal bit on the back, and slide out the wire with the metal springy bit. Do this to remove the connector from the old fan and swap it onto the new fan and you should be all set. Otherwise, I'm going to leave the process of connecting the new fan up to the reader.

Looking at the rear of the PSU, with the metal grille snipped out. Why? Well, most computers expose this grille to the world, whereas in the G4 it is hidden behind yet another plastic grille. This double-grille creates additional noise, and it's a lot cleaner looking to remove the grille from the power supply than it is to remove from the rear plastic of the machine. If you're not sure about this, don't do it! Test the machine with a new PSU first, and if it's not noisy - leave it alone. If it seems a bit too noisy, remove it.

At this point, you're finished. Put the PSU back together and re-assemble the machine.

More TimeHats!

Back in April of this year, a renewed interest on the Time Nuts mailing list developed regarding my TimeHats. The first run of them back at the beginning of the year was fairly small, only 20 units, and only about 15 of them went to folks on the TimeNuts list. They developed a good reputation and I received some very positive public feedback - prompting more interest. I posted saying that I hadn't planned on making more than those initial 20, but that I hadn't yet developed a new revision, so if people were interested I could do another run of identical units, I just needed to know how many parts to order.

The interest ended up being more significant than I had anticipated. A lot more! To the tune of about 150 as it stands today. Due to the current global parts shortage I decided against taking any kind of pre-orders (though it would have helped financially) because I didn't know if I would run into any issues delivering units. At the moment I am waiting for the second big delivery of GPS receivers and antennas - 100 in total. I have already assembled, tested, and shipped about 50 units.

I took a number of pictures along the way as I have assembled them, so I wanted to post them here as a sort of "photo essay".

The first parts to arrive were the µSD cards, 70 of them.

Next up were the PCBs and RTC modules, as well as other little odds and ends like batteries, screws, standoffs, etc.

There's lots of processing that needs to be done, lots of intermediary steps. The holes in the PCBs are slightly too small for my M3 screws, so they have to be drilled out a big larger (I do this with stacks of boards, so it goes fairly quickly). The headers from both the RTC modules and GPS modules need to be removed, and in the case of the GPS modules, the holes must be clean and clear as they are re-used - in the case of the RTC modules we use the second header that is available.

Going with full-size 40 pin headers was a mistake, even though I got them very cheap. They took FOREVER to solder. The next go around I will use much smaller headers that only use the pins I need - in this case it's only a small handful clustered at the top.

Before the modules could be soldered onto their boards, they had to be tested, so I added two female headers to a PCB to make testing quick. A great thing about both of these modules is that they can be fully tested without rebooting the whole system, meaning testing is relatively fast.

Next, it was time to start assembling! This went pretty quickly.

And before long I had 97 boards waiting for GPS modules.

It took a while, but the GPS modules and antenna finally showed up! (And I'm still waiting for more.....)

Then they needed the same testing and processing as the RTCs did.

With both modules installed, proper testing could commence. This took a while.

But once completed, they got parked in the box and are ready to ship!

Spring Cleaning!

Spring has sprung here in Maine, so it's time to clean some computer equipment.

Today, we're going to start with Jennay, my HP DL380 G9 which acts as the primary server on my network for both production and lab uses. After shutting down the lab VMs and migrating the production VMs to a temporary host, the cleaning could commence! This box had 120 days uptime prior to being taken down, which is pretty good for me.

First, we have to clean the top of the server itself, which tends to take the role of a sort of shelf in my rack. Mostly a junk shelf. It also holds our cable modem, an external hard drive, two Pis with GPS clock duties, and the UPS for the network gear. The cables on this stuff are all long enough that they can be moved aside without being powered down.

Messy DL380G9

And now it's clean!

Clean DL380G9 Top

Don't forget to install your UPS-supporting cat food container.

UPS supporting cat food container

Then we can take it outside and get a closer look at what we have. Lots of buildup on these side vents by the power supplies.

Dusty Vents

Using the shopvac with the hose connected on the back to blow (it was moved after this photo) in conjunction with a firm paintbrush to get more stubborn dust out of there.

DL380G9 Outside 1

It's really not that bad inside, but there are a few corners where there's bad accumulation, and a fine surface layer over everything that will just get worse over time.

DL380 G9 Inside Pre

Again, it's hard to tell, but it's MUCH cleaner now. Especially everything around the fans, they were caked with very fine dust.

DL380 G9 Clean

The second goal with taking this server down was to add a small fan to the onboard HBA controller. It is regularly the hottest point in the system, usually between 52ºC and 55ºC. The larger part of the heatsink is almost perfectly 40mm on each side, and there is a 12v powerpoint nearby on the PCIe riser.

RAID Controller Heatsink

It's a good fit, and there were metal tabs on the ends of the wires that allowed them to snugly fit into the large 12v connector.

RAID Controller Heatsink Fan

I also used a very small amount of hot glue on the front and rear edges to tack it into place.

RAID Controller Fan Glued

Works great!

RAID Controller Fan Working

This modification brought the temperature of the onboard RAID chip down to 42ºC - it's still one of the warmest components, but a 10º drop is significant, and should lower the thermal stress on it significantly. The next time I take the server down I may remove the module and replace the thermal interface material between the controller and heatsink.

The important parts back in place, all the other junk is in a box on the floor. Here's to another 120 days!

DL380 G9 Returned

TimeHat ❤ Nokia FYGM

FYGM and TimeHat

For the past few monts GNSS-disciplined time servers have been taking up a large percentage of my hobby time. Building and distribuiting the TimeHat went very well, and it gave me a bit of extra capital to dig into a few things that I might not have been able to otherwise, like picking up some "real" GNSS timing modules! The unit I was most interested in was the Nokia FYGM, a GNSS timing receiver made to work with Nokia cell site equipment. The FYGM has a u-blox LEA-M8T, one of the better timing-focused u-blox modules available. Lots of people buy these (and other) timing modules from decomissioned cell sites through Chinese scrappers and recyclers just to harvest the receiver, but I wanted to keep them as "together" as possible.

Unlike typical hobbyist GNSS modules, the FYGM has a some extra hardware on it, namely an 8051 MCU. I have more information on this on the wiki, here, so I'll keep this short. To start, why not simply emancipate the M8T from this board? I have a few reasons:

  • I don't want to design a new carrier for the M8T
  • The original board has high quality power supplies for the M8T and active antenna
  • It also provides excellent antenna protection circuitry
  • The included aluminium case is really nice
  • The status LEDs (driven by the MCU) are useful
  • Once the board boots, it's not hard to get the MCU out of our way

That MCU, the 8051, started as being the biggest thorn in my side. Before I had one of these units in my hands all I had to go off of was ebay listing pictures and a couple of posts on the TimeNuts mailing list, but that was enough to get started. In addition to antenna input, the FYGM has one other connector - a 12 pin DIN amphenol-looking thing. Thankfully all of the FYGMs I have found for sale inclide a completed cable to mate with this (using an HDMI connector on the host device end, with CAT7 as the cable itself), otherwise this connector could be a real pain to deal with, becuase it's not an amphenol, or anything that seems to be generally available. Only 8 of the pins on this connector are used, Ground, DC in (taking anywhere from 12 to 35v), and then three RS422 differential pairs for Tx, Rx, and PPS. Two RS422 transceivers on the bottom of the module provide this signaling. My initial intention was to try and use these as-is, so I got some hardware to work with RS422 - more on that later.

Once I got an FYGM in my hands, I started tracing all of the connectors and headers. I was disappointed to learn that the RS422 transeivers' input does not come directly from the M8T, but rather it from the 8051. This meant that it probably wouldn't be spitting out UART signals directly from M8T, something that turned out to be true. On the bright side, the four pin connector adjacent to the M8T is, in fact, UART directly from the M8T, meaning that bypassing the 8051 seemed like a possibility, and it technically still is. The ten pin connector next ot the 8051 is a programming and debugging header for that device, so perhaps one day I can read its configuration out or even reprogram it to make it more useful to me. The more immediate use that header has is the exposed reset pin - dropping a jumper between it and ground causes the 8051 to not boot at all, so through the UART pins next to the M8T I can interface with it directly, and completely ignore the MCU. I didn't end up doing this though.

Why?

Well, to put it plainly, the engineers who developed this thing had some clue as to what they were doing - remember, this device is intended to be a highly precise GNSS time source for a clock in a cell site. If we can benefit from the work they put into developing this thing, why not? When the FYGM boots, the 8051 sends a number of strings to the M8T to put it into a configuration that makes it optimal for use in its intended purpose - which just happens to be the purpose I have for it! As far as I have been able to tell, once these strings are sent, the 8051 gets out of the way entirely, it simply takes UART from the M8T, process it, and spits it out over R422. Initially this was a disappointment, but... I don't need to use the RS422 - I can run the signals straight from that UART header to the host - and that's exactly what I ended up doing.

Early on I had started to design a Pi Hat with an HDMI port, a DC in jack for 12-35v, a 5v power supply for the Pi, and RS422 transeivers for the UART and PPS signals. As much as I like the aesthetic of this, it's just not reasonably feasible. Seeing as the UART from the M8T isn't connected directly to the RS422 transeiver on the FYGM, I would have to connect them directly with some bodge wires, but this means that the 8051 has to be taken out of the loop, and for the reasons described above, I don't want to do that anymore. What I ended up doing is pulling the pins out of the eight pin JST connector, everything but ground and DC in, and I am connecting to them directly to the UART signals out of the M8T. This also lets me do some sneaky stuff. It's kind of ugly, but it works well and allows me to continue to use the DIN connector which is solastic'd in place.

FYGM Open

Again, this is ugly - but it works. If you look closely you can see the sneakyness... As you can probably tell from the picture at the top of this post, what I have done is cut the included cable down to about a foot and run it straight onto one of the TimeHat boards, feeding in Tx, Rx, and PPS just as the MAX-M8Q modules do. Power comes in through that barrel jack zip tied to the cable. If you look closetly, though, you'll see something going to the 5v pins of the TimeHat, what's up with that? Well, I spent a while think about how best to handle powering this whole mess, and I really liked the idea of integrating the Pi and FYGM as closely as possible. The UART header on the FYGM has a pin for 3v3 input, so I could power the M8T directly. The 8051 and active antenna circuits have their power power regulators though, these are fed from 6.3v coming from the main power supply on the board.

The Pi has no easy way to source 6.3v, but you know what? Turns out it will run just fine on 6.3v! I haven't spent much time at all studying the power front end on the Pi, so I just threw 6.3v on the 5v rail and sure enough, it works just fine! This may very well impact something in a negative light, but I'm just going to let it roll for now - I'll update if it causes any problems, but I don't suspect that it will. Basically, what I'm doing is feeing 16v into the FYGM's main power supply, then pulling the 6.3v back out and into the 5v rail on the Pi along with the other signals mentioned earlier. How much power is safe to sync from this 6.3v rail? Probably not a lot - but - keep in mind that I have the Pis that I use in this role configured for very low power consumption - no WiFi, no BT, no GPU, no USB devices, and the CPU is clocked down about as low as it can go. Using a kill-a-watt, I measured the whole setup to pull a whopping 1.9 watts from the wall, including all the power supply overhead.

What does this mean as far as time server performance is concerned? Well, I don't know yet. I haven't done much of that measuring yet. I just recently got my GNSS antenna splitter, so I can finally start to compare receivers using the same signal source, which is a step in the right direction. What really needs to happen next, before I can start seriously start making this measurements, is getting a GNSS antenna mounted up above the roof line. I have my mast built and brackets in place, all that's left is to actually attach it to the house - I'm still working on figuring that out, more to come shortly, I hope.

That said, even in my "less than optimal" configuration, things are looking good. The Pi here is a Pi2, and that is on purpose. Can pairing a less-than-optimal Pi with a really good GNSS receiver help? Who knows! Here's what the chronyc sources output looks like at the moment:

FYGM chronyc sources

And here's what cgps looks like:

FYGM cgps

The 0.35 TDOP is what really stands out here. This receiver's antenna is in the basement, sitting on the ledge of a casement window. Using a high-mounted helical antenna sticking out of a 2nd story window I have seen TDOP below 0.2, so I expect this to improve well beyond the capabilities of the Pi once I get it mounted on the side of the house.

Tale of Two Laptops

Last night, I traded my iPad Pro for a Huawei MateBook X Pro (2018) (hereafter "matebook") and now I'm going to spend some time comparing this laptop to my current laptop, a Panasonic Let's Note CF-SV8 (hereafter "SV8"). Both machines are very similar in some ways and incredibly different in others, so I thought I might take the opportunity to write a little bit about this. This is not a review of either machine and is probably a bit premature as I've had the SV8 for a few months and the matebook only a few hours.

Lets start with the objective boring stuff, the specs.

SV8 (CF-SV8RDAVS)MateBook
CPUi5-8365U 4c/8t 1.6GHz Base, 4.1GHz boost, 6MB L3, 15wi7-8550U 4c/8t 1.8GHz Base, 4.0GHz boost, 8MB L3, 15w
RAM8GB LPDDR3-2133 (soldered)16GB LPDDR3-2133 (soldered)
GPUIntel UHDIntel UHD 620 & Nvidia GeForce MX150
SSD256GB m.2 NVMe 2280512GB m.2 NVMe 2280
Other StorageDVD-RW & SD XC slot-
Ports3x USB3.0, USB-C Thunderbolt 3, HDMI, VGA, 1GbE Ethernet, Headset, 16v power1x USB3.0, USB-C Thunderbolt 3, USB-C 3.0 (data & power), Headset
NetworkingIntel I219-LM Ethernet, Intel Canon Point-LP CNVi Wireless-ACIntel Wireless-AC 8275
Screen1920x1200, 12.1"3000x2000, 13.9", capacitive multitouch
Dimensions283x204x25mm (11.1x8x1in)304x217x15mm (12x8.5x0.6in)
Weight1Kg (2.2lbs)1.3Kg (2.9lbs)
Battery43Wh (5900mAh 7.2v) removeable56Wh (7410mAh 7.6v) fixed
OtherIndicator LEDs, Windows Hello camera support, full magnesium chassisBacklit keyboard, fingerprint reader
Retail Price (Approx.)$2,200$1,700

So, what does this tell us? Well, these are both "thin and light" medium/high class machines from 2018, though their target audiences are very different. The SV8 isn't even sold in the US, and is targeted squarely at Japanese businessmen wanting a high end and very practical Windows laptop with good connectivity and great battery life. The matebook, on the otherhand, is sold worldwide and is targeted at people who want a Mac but want to run Windows on it for slightly less than Apple prices. It's a high end machine, but not really suitable for "traditional business use" and it suffers from the port-deletes found on most similar thin and light laptops today.

Aside from the differences in CPU and RAM (which, I think it's worth mentioning - the SV8 is available in an i7/16 config, and the matebook is available in an i5/8 config) the largest difference between the two from a hardware perspective is that the SV8 has an integral full-size optical drive, which, for a 12" laptop in 2018, is nothing short of incredible. It's not something I need or use, and in fact I have it disabled in the BIOS, but I can understand how some see the appeal. Optical drive delete models exist and are approx. 100g lighter, but they don't seem to be very common. Additionally, the matebook includes a dedicated Nvidia MX150 GPU. This is a GPU suitable for "light gaming" (eSports Titles and the like) and something I would just as soon not have. It's not possible to disable entirely in the BIOS, but it's trivial to do so in both Windows and Linux. Doing so, of course, increases battery life. Personally, I find the inclusion of a dGPU for occasional 3D tasks to be more beneficial than an optical drive. I can plug in a USB optical drive, but eGPUs are decidedly more of a pain.

I don't use a laptop as my primary machine, so lots of RAM and a powerful CPU are much less relevant to me. The SV8 has performed every task I have cared to throw at it handily, and while I haven't done as much on the matebook, I expect it to perform just as well. I have benchmarked both machines, both with Geekbench 5.3.1 and an xz compression test if the reader is interested in raw numbers.

Both machines have beautiful screens. The matebook's panel is glossy, however, because it's also a touch screen, which is not something I care for. I don't mind glossy panels, but I know that some hate them. I rarely, if ever, use a computer outdoors, and I try and avoid situations with bright overhead lighting when I can. 3000x2000 at 13.9" on the matebook is far too high a DPI for me to use at 100%, but 200% is too large. 150% feels just right in windows, but fractional scaling suffers considerably under linux, and may even be impossible when using the Nvidia GPU. I would prefer to run my display at 100% under all circumstances, but on the matebook it's just not possible for me without reading glasses. The SV8's panel, by comparison, is 1920x1200 at 12.1", and I find it very usable at 100%. There are times when my eyes are a bit more "tired" and focusing on the smaller characters is a bit of a struggle, but this can quickly be resolved by blowing up my web browser or terminal to 125-150%. Both panels are better than a typical 1920x1080 display due to the added vertical height. The matebook is 3:2 and the SV8 is 3.2:2. Both are wonderful, but the added height on the matebook wins for me.

On the question of input devices, it's no question that the matebook wins for me. The keyboard is wider with larger keys, and it has a more standard American layout that I am used to elsewhere. The keys have good travel and feel, and nothing wobbles or bends when typing. It's not the SV8's fault for having a JIS keyboard, as it is a machine primarily sold in Japan, rather it's my fault for using a JIS keyboard in an American layout. The SV8's keyboard has many keys that are specific to inputting Japanese text, which are unused by me, and I would prefer they not be there at all to make the other keys larger. There is a configuration of the SV8 that is sold in Singapore which has an American style keyboard, but I have not been able to find one of these yet. I also suspect if I had smaller hands I would like the SV8's keyboard more. The SV8 keyboard does win out in a few ways, though: it has a contextual menu key, which I use daily, it has dedicated Insert/Delete keys (the matebook only has delete), and the arrow keys are in the "normal" inverted-T configuration, rather than the mushed macbook-style that the matebook adopted. The feel of the SV8 keyboard is "fine", on the mushier side but not bad. It also feels very rigidly affixed to the case. The matebook's is also backlit, which I appreciate; the SV8's is not.

I almost always use a bluetooth mouse when using a laptop on a table, but I'll use the trackpad plenty around the house or when traveling. The matebook has a gigantic glass covered trackpad, much in Apple's style, and it feels great and is very responsive. The SV8's trackpad is also very responsive, and it's unique circular shape is interesting, but it is very small, which can be frustrating at times. The dedicated buttons of the SV8 are nice, but missing them on the matebook isn't a dealbreaker. Something I wish both had was the ability to turn off the trackpad from a function key. If I'm using a mouse, I often don't want any input from the trackpad.

The matebook's thinness causes it to loose the I/O battle without question. A single USB3-A, two USB-C (one of which is TB3) and a headset jack. That's it. Not even an SD card slot. The SV8 on the other hand comes in with a full compliment - three USB3-As, a USB-C for TB3, HDMI and VGA, ethernet, and a dedicated barrel jack for power. The SV8 also has a full compliment of indicator LEDs: power status, lock keys, and activity of HDD and SD while the matebook only has a charging LED on the side. USB-C charging is an option for both machines - the matebook requires it with no alternative, and the SV8 supports it as long as the machine is either running or in standby. For some reason it won't charge from USB-C if it's powered off - I haven't figured out why. Both support Windows Hello if you're into that sort of thing - the SV8 has the IR camera while the matebook has a fingerprint reader on the power button. I don't use either. The webcams on both are good, though the SV8's is clearly better, full 1080p. The matebook's is 720, and it pops up out of the keyboard between the F6 and F7 keys, which is a very peculiar feature. It does enable the screen area on the matebook to completely fill the lid, which is very attractive. The matebook has fairly full-sounding speakers which can be incredibly loud, which is something I find frustrating. In Windows I find the 10-15 volume level to be appropriate. The SV8's speakers are "fine" but definitely not something I would want to use for listening to music, contrary to the matebook. I haven't used the microphones on either, but I imagine they're both pretty bad, but acceptable in a pinch.

I don't know how Huawei's batteries track over time, but I don't have a tremendous amount of confidence in it's long term capacity. The SV8, on the other hand, I expect to retain near-original capacity for years, as has been reported by other Let's Note owners. Panasonic is just really good at batteries, go figure. I have never needed to go more than about 5 hours on a charge, and both machines will do so easily. The 43 watt hour battery in the SV8 is reported to last up to 13 hours under light duty loads, and I can believe that. The matebook is advertised as lasting 12 hours, which I do not believe. Reviewers have placed it at the seven to nine hour mark, which as I have stated is plenty enough for me. I don't know if I will be able to get a replacement for either, should I ever need one.

So, aesthetics. The matebook is boring. Lots of people will probably find it to be very sexy and attractive, but it's just a 13" MacBook Pro clone. It does a good job being a MacBook clone in that it feels very solid and the fit and finish is excellent. Pretty, but boring. The SV8 on the other hand is a cute little pragmatic powerhouse that many people find to be tremendously ugly. It's true that the aesthetics of Let's Note laptops haven't changed significantly in 20 years, but Panasonic is clearly taking a "if it ain't broke don't fix it" approach to their laptop design, and I am thoroughly okay with that. The chassis is composed entirely of magnesium, so it's very strong and light. The lid has an interesting wavy design in the top that is designed to distribute weight that might otherwise crack the display. When you pick up the SV8 you are immediately surprised at how light it is, and you suspect it's made of thin plastic like a netbook, but it's not! The SV8 also has a top mounted hinge, which I greatly prefer to the matebook's macbook-style wrap-around hinge. The matebook is "sleeker" though - thinner with no protrusions. The SV8 is much thicker, and the way the battery and feet stick out from the bottom causes them to often get caught on something when taking it in or out of a bag. Additionally, the strange footprint and thickness of the SV8 makes finding a suitable small sleeve or case a challenge, whereas the matebook is much more of a generic 13" laptop.

Conclusion? I don't have one yet. They're both good laptops, and for the foreseeable future I'll continue to use both in varying roles. I look forward to traveling with both when Global Pandemic is over as I would like to have more time with each on the road. I can see the SV8 being more of a desk queen, living beside my desktop in a very dignified role. The matebook, on the other hand, is a beater - if it falls off a table or my daughter spills chocolate milk on it, well, that's why I have an accidental damage rider for laptops and tablets on my homeowners insurance. I do not know if it would be possible for me to get another SV8.

SV8 and Matebook