Old build POSTs outside case, won't POST in case

[Towncivilian]

My friend recently recapped my abit BX133-RAID motherboard. It posts and works fine outside the case on a cereal box, but when I install it in the case (new old stock Antec SLK1600), it powers on but has no activity. I tried two different power supplies, two different graphics cards, absolutely nothing else attached (not even front panel header / PC speaker), went down to one stick of RAM, cleared CMOS half a dozen times and also changed the battery...

I verified that there are no extra standoffs present underneath the motherboard. I used the standoffs and screws that came with the case. The I/O shield is installed and none of its fingers are making contact with the ports.

I will try reseating the CPU in case it somehow creeped out of the socket a little. Does anybody else have any suggestions?

[ratdude747]

Re: Old build POSTs outside case, won't POST in case

Screws or the like behind the mobo would be my guess but it sounds like you checked that. Also, check for uncut or too long leads where you recapped...

[stj]

Re: Old build POSTs outside case, won't POST in case

+1
look more closely at the posts and consider trying paper washers.

[Agent24]

Re: Old build POSTs outside case, won't POST in case

Check you don't have one of the tabs of the I/O shield poking inside a port somewhere

[kc8adu]

Re: Old build POSTs outside case, won't POST in case

screwheads shorting traces?

[Towncivilian]

Re: Old build POSTs outside case, won't POST in case

Leads on underside of mobo are fine, but I'll double check. I am using the screws and standoffs that came with the case, and the screwheads do not appear to be contacting any traces or other components when installed. I/O shield is fine as said in the first post. I even tried removing the I/O shield and it made no difference.

[Sparkey55]

Re: Old build POSTs outside case, won't POST in case

Is the motherboard warped by even the smallest degree? Mobo OUT of case works, mobo IN case; screwed down flat doesa not work.

[stj]

Re: Old build POSTs outside case, won't POST in case

try with only a couple of screws

[Sparkey55]

Re: Old build POSTs outside case, won't POST in case

My friend recently recapped my abit BX133-RAID motherboard. It posts and works fine outside the case on a cereal box, but when I install it in the case (new old stock Antec SLK1600), it powers on but has no activity. I tried two different power supplies, two different graphics cards, absolutely nothing else attached (not even front panel header / PC speaker), went down to one stick of RAM, cleared CMOS half a dozen times and also changed the battery...

I verified that there are no extra standoffs present underneath the motherboard. I used the standoffs and screws that came with the case. The I/O shield is installed and none of its fingers are making contact with the ports.

I will try reseating the CPU in case it somehow creeped out of the socket a little. Does anybody else have any suggestions?

Really need to see some photos of the recap job. What brand and series of caps were used? are they genuine? where they bought on eBay? Has your friend have experience recapping motherboards? What were the old caps that got replaced?

[selldoor]

Re: Old build POSTs outside case, won't POST in case

Have you tried it outside the box after you tried it inside?

Try preheating with a hairdryer might be a bad joint?

[Towncivilian]

Re: Old build POSTs outside case, won't POST in case

Caps used were Panasonic FM series bought from Mouser. I'll try to get some photos up soon. Friend has recapped several mobos before. I don't remember what the old caps were but they were not visibly bad, I had it recapped preemptively.

I did try the mobo outside the case after being mounted in the case and it POSTs. I will check for warping of the mobo and try fewer screws.

[selldoor]

Re: Old build POSTs outside case, won't POST in case

I did try the mobo outside the case after being mounted in the case and it POSTs.

Was that using the same power supply , ram and 0n/off switch leads from the box and monitor.

[Towncivilian]

Re: Old build POSTs outside case, won't POST in case

Yes, identical parts inside and outside the case. Haven't had a chance to try anything else yet, I probably will later today though.

[Towncivilian]

Re: Old build POSTs outside case, won't POST in case

Figured it out! A pin on the processor has broken off. It turns out the board no longer POSTed outside the case ... so the one time it did POST out of the case, the pin must have been making intermittent contact. I believe the pin broke when the computer took a small fall in my vehicle. I had it standing upright on the rear seat and had to stop relatively quickly, causing the case to fall down on its side. This must have resulted in the broken pin.

Well, first of all, this AMD heatsink is not a good choice for this processor:


Spot the missing pin:

Bonus points to whoever figures out the function of that pin. How I wish it were just a ground

There it is!


Luckily, a magnetic tipped screwdriver pulled the pin out of the socket with ease.


It seems that my faithful Pentium !!! 1000EB has ran its last instruction. Ah well, the board lives on... time to find another socket 370 processor. All I have here is a Tualatin. I know I can try to mod the processor to work on this board, but I don't feel like breaking any more pins off or messing around with a conductive pen tonight.

A couple (probably terrible) photos of the recap job:


(large version)


(large version)

I know, I need to get a chipset heatsink. As you may notice based on the residue, the previous heatsink was superglued on at the four corners, with some thermal grease in the middle. I haven't yet found a heatsink with mounting pushpins that fit this board's spacing, and the original tiny green abit chipset heatsink is nowhere to be found.

The two block pins in the black IDE sockets were removed. I don't know why they were even there, they caused so many headaches trying to find a cable with the block pin open.
The two fan headers right next to each other don't work. I've read that it could be a problem with the transistors (the four very small ones right next to the headers) but I haven't been able to confirm that, nor have I been able to find replacement transistors (the text on them is damn near microscopic). The third fan header near the CMOS battery works fine still. I think the dead fan headers should still sense RPM though, so they are still useful as long as I power fans using the power supply.

Also, in the processor socket photo above, you can see the 12 SMD caps which were added to the board. Looks like I should clean up some of that left over flux before I install another processor. Anyway, I'll go reinstall the board back in the case now. Thanks for all the suggestions, everyone! I know I'd get laughed off some other boards if I posted my troubles with something this ancient.

One more mildly interesting fact: the Antec SLK1600 case I bought off eBay was new-in-box. It has an Antec SmartPower SP300 power supply which has probably never been powered on except for testing at the factory. I opened it up to take a look and a cap on the secondary side is bloated, leaking electrolyte. Is this a power supply worth recapping? I've read of a fan thermal control resistor modification for these power supplies too, so if I go ahead with the recap I'll do that too.

[Agent24]

Re: Old build POSTs outside case, won't POST in case

Edit: Never mind. The site I was looking at was wrong. Looking at Intel's Datasheet it's pin D60 that's broken. (Page 68 for pinout)

I wonder if you could solder a piece of wire onto where the pin broke off?

[kc8adu]

Re: Old build POSTs outside case, won't POST in case

if it were here i would put the tiniest dab of flux on it and try to flow it back on with a air pen.
just for practice to be ready for the repair that counts.

[Towncivilian]

Re: Old build POSTs outside case, won't POST in case

I did save the pin. I'll have my buddy give a try at reattaching the pin somehow.

[stj]

Re: Old build POSTs outside case, won't POST in case

what cpu was it anyway?
something decent?

[Towncivilian]

Re: Old build POSTs outside case, won't POST in case

what cpu was it anyway?
something decent?

I don't think it was anything spectacular, I think it's a Pentium 3 1000EB (Coppermine) or the 1000 Coppermine-T version.

It seems that I can just pull a few pins from the Tualatin CPU I have and it will work without any further modification to the processor, at least on my BX133 board: http://digilander.iol.it/grandecigno/Tua_BX_3.htm
According to that page, I'll be able to adjust the voltage up to 1.7v through the BIOS, if necessary.
I hope mine is an S version with 512kb of L2 cache, it's been so long since I acquired it I don't remember what it is.

[Towncivilian]

Re: Old build POSTs outside case, won't POST in case

I pulled the three pins mentioned in my link above on my Celeron 1000A Tualatin core and the board boots with it, in the case with everything connected. I already had the modified BIOS with Tualatin microcode installed, but the board still detected it as a Pentium III 667mhz. I manually raised it to 1.0ghz with 133FSB. I haven't installed any OSes yet on the build, couldn't find any blank CD-Rs! I bought a Pentium III-S 1.4ghz / 512k L2 and a new tall Zalman chipset heatsink from eBay today. Maybe I should have gotten a larger case? The SLK1600 seems kind of cramped... wish I could find one of those tall beige server towers!