Emergency PC Motherboard Repair/TroubleShooting Guide - PC won't boot, WHY???

[NightWolve]

Synopsis: You install a new 4GB Radeon video card, the RX 460 in your PC's PCI Express slot, you get the drivers installed, everything seems to be working fine, but after you reboot your computer, it no longer boots, no video output, it stays stuck... Uh-oh, so what went wrong, why ??

TroubleShooting Steps I went through:

1) Rule out the video card. I swapped back the old video card, but same problem, the PC would get stuck... No video output, won't boot... Uh-oh, it won't be as easy as that....

2) Now I'm in a panic thinking my motherboard is dead and that I'd need a new computer... I tried to think, what, why is this happening...? Then, I spotted a ruptured capacitor near the PCI Express slot! AHA, I thought!!!!!! Maybe the EE skills I learned from TheSteve will help, so time to pull out my soldering iron, my cap kit, etc., and see if I can save this 2008 motherboard!!!!! After I unscrewed the whole motherboard out, I got to work!

a) Presenting, the victim capacitor:



b) After much difficulty, I desoldered it off:



c) For kicks, just to see how much it failed, I used my VC99's cap testing feature to measure its remaining capacitance ability (it's a 470 uF cap, so...):



Yep, almost total failure, from 470 uF down to 69 uF... NOT GOOD!!!! That cap was terminated!

d) Being a perfectionist, I wanted the best new capacitor from my kit and that's what the VC99 is great for, after measuring about 20-30 of them, I chose this one:



e) New cap installation results:



f) So, after putting my PC back together again and turning it on, was I successful.... DOH!!! SAME PROBLEM!!! NOOOOOOOOOOOOOOOOOOOOO!!!!

3) WHAT NOW ?? Then it occurred to me, I tried to think, the only other time I can remember that this happens is with bad memory modules, the PC stops, beeps about a problem, a card not inserted fully or memory cards... I removed these 2 newer 1GB DDR2 modules I had installed...rebooted and EUREKA!!! The computer would boot again... YAAAAY!!!

Thankfully, my neighbor had given me a Win7 box, I took out 2 GB modules, and got my rig up to 6 GB now running with Win7 64-bit, so the swap file is obsolete. I got other 2 GB modules from my other neighbor too, so those went back to the old Win7 box I was given as a why not (I did upgrade it to Win10 and will have it around for testing/development).


OK, moral of the story, I took the whole computer apart to replace a dead capacitor, which IS a good thing, but while that looked like a CLEAR problem and should be corrected, it really wasn't, 1 or 2 memory modules had gone bad...

That's my story, if it ever helps you out, you're welcome.

And...I'm out!

[blueraven]

Far Out!

Glad you're back on the road.

I have a machine that's very similar to that, a 2007 Dell desktop that I bought a spare motherboard for. It's still running Windows 7, and I had a similar RAM issue and ended up upgrading the unit to either 6 or 8GB which corrected the same hangup.

I'll look for this if I upgrade the graphics card. Thanks for the post.

[NightWolve]

Now my problem is that this 4K video card is so much more powerful than the 2008 triple-core 2.1Ghz CPU... Looking for a cheap quad-core upgrade on eBay in the coming weeks (sucks that it's an AM2+ board, harder to find good upgrades as opposed to AM3)... I'm very close to having it run 4K videos without being choppy, that's what it desperately needs.

ProTip: Make sure your new video card says the HDMI output is 2.0 compliant so you don't have to play any games with the ATI patch utility or the Custom Resolution Utility to try to hack your way to 4K support.

[PunkCryborg]

Xseed employees probably sabotaged it

[BigusSchmuck]

Now my problem is that this 4K video card is so much more powerful than the 2008 triple-core 2.1Ghz CPU... Looking for a cheap quad-core upgrade on eBay in the coming weeks (sucks that it's an AM2+ board, harder to find good upgrades as opposed to AM3)... I'm very close to having it run 4K videos without being choppy, that's what it desperately needs.

ProTip: Make sure your new video card says the HDMI output is 2.0 compliant so you don't have to play any games with the ATI patch utility or the Custom Resolution Utility to try to hack your way to 4K support.

I *might* have some am3 boards floating around if you want to save some $$$. They will take am3+ too.

[NightWolve]

Well, what I would really want is acceptable AM3 CPUs that still can work with DDR2 memory. If I swap in an AM3 board, the 6GB DDR2 RAM I have now goes bye-bye and I'll need more money to spend on DDR3 RAM as well as worry about it fitting in the case.

It appears some AM3 CPUs might work on an AM2+ board as they have dual support for DDR2 and DDR3 RAM. Just gotta research this more. Current info: it's an AMD Phenom Triple-Core 8450 2.1 GHz, and Socket AM2+ (940 pin). Any help on a replacement CPU would be appreciated. Hoping to get those 3.6 Ghz quad-cores if they can work.

Xseed employees probably sabotaged it

[BigusSchmuck]

Well, what I would really want is acceptable AM3 CPUs that still can work with DDR2 memory. If I swap in an AM3 board, the 6GB DDR2 RAM I have now goes bye-bye and I'll need more money to spend on DDR3 RAM as well as worry about it fitting in the case.

It appears some AM3 CPUs might work on an AM2+ board as they have dual support for DDR2 and DDR3 RAM. Just gotta research this more. Current info: it's an AMD Phenom Triple-Core 8450 2.1 GHz, and Socket AM2+ (940 pin). Any help on a replacement CPU would be appreciated. Hoping to get those 3.6 Ghz quad-cores if they can work.

I have 8gb of ddr3 ram at home too. I know I have two am3 boards, but it will depend if you want on board video or a seperate video card (which incidently I have as well). I'll do some testing with it this weekend if you are interested. I think I have a am3 AMD Athlon X4 as well.

[Psycho Punch]

After all that effort you deserved to have the computer working again.

Me? I would just dump it into the Atlantic and buy another one. I'm just not good with soldering.

[NightWolve]

After all that effort you deserved to have the computer working again.

Me? I would just dump it into the Atlantic and buy another one. I'm just not good with soldering.

Ah, but you missed the twist at the end...all I had to do was pull out 2 of the newer RAM modules... One of them went bad, not sure which, but my neighbors had given me better ones (2GB modules, whereas mine were 1GB) so now I went to 6GB total. It's good that a failed capacitor was replaced for proper coupling (ask steve), but the computer still wouldn't boot after all that trouble...