Motherboard will only post 1/5 of the time

[brundlefly76]

I have an Asus P5N-E SLI, had it for years. Currently, the motherboard will only post 1/5th of the time, I just have to keep power cycling.

When it does boot, it runs perfectly fine, (except there are some awake from sleep issues I havent bothered to debug yet).

I dont mind replacing a part to fix this, but can't figure out whether its the power supply or the motherboard.

When I power it on and its fails, it looks like this:

-Black screen
-Fans on full blast
-Video card power problem beep sequence

When I'm successful, the fans immediately go from full to normal, and everything is fine.

I've tried turning all sorts of knobs in the bios, checking cables, DIMM seating, Video card seating, nothing seems to make a difference.

Note: I have video card connected to iMac target display via card's built-in mini-displayport.

If anyones got any tips on next steps I would appreciate it.

 

[Twinrehz]

Problems with POSTing is usually (though not always) related to the motherboard. If you have another MB or PSU to test with, you should try that. You mention video card power problem beep sequence, my guess would be it's the PSU, but as I said, get a different MB or PSU to test with. Maybe you can borrow it from someone, if you don't have extras yourself.

 

[cl-scott]

My initial thought is that this sounds like some classic symptoms of bad caps. Given the age of that board, I wouldn't put it past being at the point some caps are failing.

If my thought is correct, then the problem will only get worse over time. The upside is that if you're a crack hand with a soldering iron, or know someone who is, it's a relatively inexpensive thing to fix if you can find some capacitors of the same specification. The downside is that if you're NOT a crack hand with a soldering iron, and try this yourself, you'll probably just make things worse. So in that latter case, it might just be time to consider either retiring that system or trying to find another board to replace it.

http://www.badcaps.net/pages.php?vid=5