Monitor goes dark then returns, mouse cursor freezes afterwards

[videobruce]

This isn't going to be easy to describe, but here goes;

I believe it is a thermal problem with the video card, but I'm not sure. After the box has been on for 30-60 minutes (or so) the monitor goes dark for a second then returns. This happens a few times and if it really gets bad (more frequent) the dark periods get longer that the monitor goes into standby mode then returns with the mouse cursor frozen that I have to reboot to get it back.

I know it's not the monitor, it's the video card not sending a signal to it and somehow also locking up the mouse (keyboard is ok).

This happened after installing S/W for a HP S20 photo scanner, BUT I don't think that is the problem because on my other bootable drive (in the same box) the problem is there but not as bad. It might be making it worse, but I don't think it is that easy. I'm also not sure it is the card itself, thought it is the card that is not sending the video signal to the monitor.

Before I swap cards, anyone have any ideas? Here is the system:

Win 2k w/sp3
Epox 8RDA nForce 2 MB (latest bios and nForce 2 UDP)
AMD 2100b
2x256MB Corsair PC2700
Saphire ATI Radeon 9100 (latest ATI driver)
HP S20 scanner
Kodak DVC 325 camnera
Creative PC-Cam 600
SB Live value
Antec 330W Tru Power PSU

Device Manager ok
No viruses

I have pulled and reseated the video card, memory, processor (added a little more compond).
I have not overclocked anything.
No overheating apparent on processor or video card.

As I write this the system has been on for over 2 hours without a single incident (so far).

[Brainchild]

the easiest way to find out is to swap the video card, if ya have one extra,and see how it acts.
It does sound like a card getting flakey

[Bruneau]

If you're pushing your fsb too hard it may be a RAM or vdd.(chipset voltage) problem. That will give you video errors also.

[videobruce]

Update........

I swapped the video card and removed the scanner software including deleting enum registry entries that were left behind and the problem is still there.

Now.......is it the processor, MB, PSU or coruption left over from the software install of the HP scanner??

PS: FSB is 133. I'm NOT overclocking anything!

[videobruce]

How about a KVM switch thrown into the mix???
How about a bad connection into/out of the switch?

That's what it looks like as of now. I wiggled (nothing was loose or not shoved in all the way) the plugs on the switch after I noticed the LED on the switch flickering when I lost the video to the monitor. (There is nothing connected to the other port other than the cable for another box as a conveinence feature.)

Really sucks since I thought it was the processor so I ordered a 1.7 XP for $49 from Newegg with the optional 1 yr warrenty (30 days standard). Guess I have a spare now................

[no1_vern]

Frist boot into safe mode and try that. If that works its the drivers. if it doesnt work remove KVM, try to Boot into safe mode, if that doesnt work try a diff monitor.

[videobruce]

It seems to be ok now. It's not the monitor, again the mouse cursor was affected also.
There is no software or drivers for the switch. It's just a 2 port switch that you add your cables to between the MB ports and the switch. Nothing fancy!

http://aten-usa.com/products/product.php?Item=CS12

[no1_vern]

I meant the drivers for the scanner. But its ok, what, after you removed the KVM?

[no1_vern]

Did you try to boot into safe mode?

[videobruce]

No on the safe mode.

The LED on the switch flickered at the same time the monitor went dark. I assume that power was lost to the switch momentary (it is electronic that can be controlled from the keyboard also). The switch gets fed power from the keyboard connector.