Foxconn WinFast C51GK8MA revived

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Time for a little story:

So I was given this board as "bad" since it wouldn't work with PATA optical drives. Turns out this board doesn't like long IDE cables. That was a lucky fluke I used a short cable, but now that it's known easily worked around. Had some single core 939 Athlon64 3200 in it. Didn't really overclock that well, but I didn't really try. Maybe better memory would help but it just got set in the corner.

Separately I was also given a Tyan workstation board with an Opteron 165 that apparently liked to "desolder" it's Nvidia chipset from the board. I managed to use a torch on the chipset heatsink twice to "reflow" the chipset back onto the board. The third time I had to repeat this process I heard a loud *ping!* and she was dead. It was a nice board, but it was always cranky. However from that loss I now had a loose socket 939 Opteron 165. Unfortunately it's also the lowest of the low of that line, crippled by a really low multiplier. You'd have to find a board that tolerates a really high bus speed to overclock it. I doubted I'd chance on one of those enthusiast boards. The only other 939 board I had was this generic looking mATX board in the corner that doesn't like long PATA cables. Might as well try it out right? It'll at least be doing something other than the chip decorating my desk. I didn't expect much...

Little did I know that this much ballyhooed WinFast C51K8MA ends up being a perfect match for this low-multiplier Opteron.

So after limping this board for about 2 months with known bad caps that were getting horribly worse I finally had time to recap it. Signs of this were pretty obvious, the high pitch choke squeal got progressively worst at POST. Eventually you would have to wait for the motherboard to "cool down" for it to POST at a given speed. Toward the final stages the maximum HTT speed you could post at steadily decreased. I knew it was bad, but finally it wouldn't even get past the video card BIOS POST at stock.

I'd been meaning to recap it for.. oh forever. But I finally got my butane torch back just four days ago. And just in time too. I use the torch to desolder with - risky and stupid probably, but it's just easier for me with these annoying "lead-free" RoHS solders that won't melt for anything

But yes! Thank you badcaps.net for allowing individuals like me to easily buy small lots of capacitors for situations like this! Disaggregation rocks!

I need to find my decent camera to get some pics, but the offenders were our favorite purple and gold OST RLX buddies.

Technically:
OST
6.3v
3300uF

RLX
105 C
O552

Replaced with SAMXON 3300uF 16v caps from here. Yea I know 16v isn't needed, but when I made my bulk order I made everything 16v so I could use them about anywhere

I hope to get some pictures of the board/rework soon. I need to remount the heatsink anyway. But I just had to post some brag/inspirational pics for people.

It's worth your time to keep your old hardware alive! Plus buy more caps from badcaps.net... everyone needs more caps =)

But yea, I also am a fan of Rosetta@Home distributed computing - which means my computers get run 24/7 at full load. Great for continuous stress testing =D But for purposes of this thread, you can see how 16 days ago the machine went into "nerf stock mode"... lets see how it recovers! Continuing proof I say. Also this computer is used as the wife's machine, so it has to be an "all arounder" ... basically I like keeping old hardware in the running as long as possible

http://boincstats.com/stats/host_gra...tta&id=1118863

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Re: Foxconn WinFast C51GK8MA revived

Did this topic come off too much as a "look at me!" post? Is there any interest for pictures?

Sorry if it came off as such.... it really was not my intention. When the batteries charge for my ancient camera I'll get some pictures of the rework... but even that is of limited value since I stupidly didn't take pictures of the "before" to compare to.

Also a step by step of my capacitor removal technique is likely an example of how NOT to treat electronics. Using a butane torch on the back of a PCB is pretty much a recipe for disaster. Plus I end up drilling out the capacitor holes afterward instead of leaning how to properly use a "solder sucker" or using solder wick correctly. So I'm basically begging to destroy a solder pad/trace eventually by drilling, let alone outright burning/bubbling the board to begin with. Bad habits/techniques which don't need to be presented as a "good way" to do things if someone was wanting to try this for the first time.

I suppose trying to evangelize for people to give fixing their own stuff via badcaps.net is rather pointless too... anyone who has found the site looking for a source, or even a reason of "why did my device stop working?" rather than just throwing it away is already going to be pre-biased to wanting to fix their own stuff. So it's not really needed to attempt to motivate visitors to go ahead and try it.

If your here, you already know why you are.

Attached is a really bad "pre-pic" of the board that is essentially worthless (no photo-flash = suck). Since I need to pull the board (hopefully this weekend) to remount the heatsink and clean out the dust - I'll get some pictures of the nitty-gritty, if only to "finish what I started" here.

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Re: Foxconn WinFast C51GK8MA revived

Don't worry, you're not showing off too much. We've all been excited over bringing hardware back from the dead.

A word of caution, though it appears to be a bit too late. Capacitance and voltage aren't the only specs that matter when replacing capacitors. There are also ESR and ripple current handling to consider.

RLX has the following specs for 6.3V 3300uF:
Size: 10x25 mm
ESR: 14 mOhm
Ripple: 2780 mA

When selecting a replacement, you want the same or more ripple handling, and the same or less ESR.

You mention you bought a 16V 3300uF Samxon capacitor from badcaps.net. The only series badcaps.net sells in that value in Samxon RS. That particular capacitor is a custom order size 10x30mm and isn't on the data sheet for RS. However, the specs we are concerned about (ESR and ripple) depend on the physical size of the capacitor. (Strictly speaking, it depends on the voltage rating too, but PC caps don't have a wide range of voltages, so just can size for PC purposes.) The specs for Samxon RS in 10x30mm are:
ESR: 40 mOhm
Ripple: 1675 mA

So, this is not an ideal replacement. The ESR is nearly 3 times as much, and the ripple handling is only 60% of the original. It may work well enough for now, but it may not be reliable over time.