PSU vs MB issue

[Baellit]

Recently my desktop has been experiencing what I had assumed to be a natural decline in performance. I have owned and put this comp through the wringer since mid 2007. Just recently, however, the computer has begun to have minor seizures with mouse movement across the desktop as well as locking up during gaming sessions. Just yesterday I was in the middle of a game when the computer began to severely chug, the cpu spiking several times to 80 or 90% and then coming back to a normal range. A couple minutes later, the entire computer shut down without so much as a beep or a warning and has not even powered on since then.

--symptoms--
-Computer will not power on, no fans, no lights, nothing.
-Prior to boot fail the computer shut down while running about 30-33c, but the computer has run hotter before with no ill effects once I turned on the secondary cooling.
-On last "reasonably" successful bootup that passed the POST and got to the windows desktop, had to press F1 to pass error message "CMOS error - defaults loaded."
-Prior to that, computer had difficulty recognizing that there was a harddrive installed, solution was unplugging one of the cd drives and letting out slack in the harddrive connection wires.
-During use, the computer had visual lag with the mouse cursor moving across a blank desktop.
-Over the past four or five days the computer has been exhibiting severe lag spikes in CPU power consumption, spiking to 99% several times and then shutting down or locking up.

--specs--
M2N-Sli board
dual 8800 Nvidia GTX video cards
2 1gb corsair ram sticks
320 hitatchi sata hard drive
580w Black Steel PSU


Later today I plan to try switching out the PSU, but I am not sure that I have a matching PSU around. I would like to be optimistic and just have to replace the PSU, but I can't help but have a feeling the mb will be the ultimate sink. I have run this system for several years with no problems, however, this past week has put to the lie that assumption as it would appear something has gone up in smoke.

[brutis]

Welcome to the AMDZone!

It sounds like it could be the PSU but also check the MB for bulging or leaking capacitors.

Let us know what you find out.

[Am486DX100]

If you haven't changed out the CMOS battery, then this part would be overdue too. It never hurts to have a spare anyway.

I'd be tempted to remove one of the video cards...until resolved.

[mdk777]

Dust and heat issues can cause these symptoms.

However, if this is the cause, it has most likely already caused damaged.

Concentrated heat causes exponential wear rates.

You were looking for a reason to upgrade to a new system anyway, right?

[Baellit]

I have pulled the PSU, however, I do not have an SLi PSU laying around so I'll have to make a trip to my friendly neighborhood price gouger and pick one up. I pulled one of the cards to try and see if it was a load issue, but boot up still failed spectacularly. As far as the MB is concerned, I can't see any bulging or leaking capacitors or any discoloration of the circuitry. Additionally, I tried jumping the PSU with a fan attached, but no dice. Hopefully this will mean just a PSU replacement.

I'm in the process of getting parts for a replacement pc, but I have to come to a decision about SLi and crossfire vs a single card system. To date, my impression of the SLi is that it is more trouble than it is worth as the initial setup was a nightmare.

[mdk777]

'm in the process of getting parts for a replacement pc, but I have to come to a decision about SLi and crossfire vs a single card system. To date, my impression of the SLi is that it is more trouble than it is worth as the initial setup was a nightmare.

Single card will always be the sure bet. (crossfire and SLI will always loose something in scaling. How much depends on the game, and how well it is optimized in the drivers.)

Mid to high end is always the best bang for the buck.(for example AMD 6950 and NV 560 TI) SLI is only needed if you want insanely larger screen sizes and the highest enhancements.