Soyo P4RC350 not POSTing -- suggestions?

[macgyver]

Here's the story:

This is a Soyo (SY-)P4RC350 ATI RADEON 9100 PRO IGP/IXP150 chipset based Socket-478 motherboard that I bought some time ago and shelved for the time being. This weekend, I pulled it out to start setting it up for a project. I was hoping to use it for a small media-extender type installation, running Windows XP.

First, things went well -- mostly. I was able to install Windows fine and after spending about a day or so digging out drivers from AMD/ATI, CMI, and VIA for the components (now that Soyo has gone bust). I got it to a point where I could install the software. That's when it starting doing randrom crashes/reboots, which I attributed first to a driver issue (the ATI chipset is known to not be the most stable). I started to restore to a clean Windows install (using disk images I made along the way), I was in the process of debugging when I had to leave for the day.

The next morning, the board would power up, but no longer POST.

I've replaced the CPU, RAM modules, power supply, hard drives, etc. with tested and known working parts (as in they boot fine in another Socket-478 board right now). I've reset the BIOS countless times, even left the board overnight without the CMOS battery and off ATX power to fully drain. I've checked for shorts, even removed the board on its own. No luck.

I do have a PCI-based hex code diagnostics card -- it never goes past the default "00" display, meaning the POST just isn't happening. However, there is power to the board -- the power LED on the motherboard (not the system power LED leads) powers up as soon as the ATX power supply is connected, and the board (CPU, CPU fan, peripherals) power up upon hitting the power button...just no POST.

Any suggestion before I chuck this and/or start salvaging parts off it? What components would you check? The caps all look fine and nothing appears damaged.

Thanks!

[PCBONEZ]

Re: Soyo P4RC350 not POSTing -- suggestions?

Is this thing loaded with silver caps?

[macgyver]

Re: Soyo P4RC350 not POSTing -- suggestions?

Indeed. They are all SACON brand, various capacities all over the board -- I figure about 30 - 40 of them.

I see no visible damage -- e.g., no blown seams on top, no leaking electrolyte, no "pushing up"/"tilting" from a bottom leak, but it's entirely possible they failed internally.

The behavior of the motherboard prior to going (well, essentially) dead was exactly on point as those described in the Wikipedia article at http://en.wikipedia.org/wiki/Capacitor_plague#Symptoms re: this whole mess about the crappy caps flooding the market. But again, I do not see any visible damage/burn/leaks.

Thanks.

[PCBONEZ]

Re: Soyo P4RC350 not POSTing -- suggestions?

SACON is aka GSC and they don't always bloat.

On Soyo [only] I've seen silver OST, Evercon, Sacon, and Capsun all with the same abnormality in the vent [the vent is stamped AFTER the sleeve is in place so the edge of the sleeve is pushed into the stamp mark - very unusual for any brand] which suggests to me they all came down the same assembly line regardless of the brand marked on them.

[macgyver]

Re: Soyo P4RC350 not POSTing -- suggestions?

That's correct -- on most all caps, the top stamp (in the shape of an "X" or "K") runs over the (what I assume is heat-shrunk) sleeve, usually a mm or two onto the inner circumference that wraps around the top bit. Scanning over a few other non-Soyo components and boards I have lying around, I noticed this is indeed unusual.

So, I guess it could indeed be the caps. I'm divided at this point on whether or not to spend the effort to replace the caps, which I could do. Gathering replacements and the work may just not be worth the effort.

On the other hand, if there's someone here who could use parts off this board for theirs, perhaps it might go to that use...

[ratdude747]

Re: Soyo P4RC350 not POSTing -- suggestions?

my ma's s478 soyo was sacon'd. too bad it was a "lite" model with a lightning zapped pci slot, so it got shitcanned for parts.

[dbs]

Re: Soyo P4RC350 not POSTing -- suggestions?

Why not replace them? - it's good practice and the board will most likely work - Sacons have to be one of the worst brands ever - maybe second to fuhyghhiii - I had both brands in one system - Soyo board and Antec PSU - both working great after a recap thanks to the knowledge from this site

[macgyver]

Re: Soyo P4RC350 not POSTing -- suggestions?

It's not that I'm averse to getting my hands dirty... As an engineer, I've done my fair share of soldering, but nowadays I unfortunately don't have the time to track down, order, gather replacements and do it. I can get a newer, better board for ~$30 and my time is worth more than that.

But I do hate to see otherwise good stuff go to waste... I'll leave this post here in case someone stumbles upon it and needs the board for other working parts, sockets, etc.

[bigbeark]

Re: Soyo P4RC350 not POSTing -- suggestions?

Please be sure to check the voltage on the button battery.

I have experienced the flat battery causing no post on both Soyo and Gigabyte motherboards.