View Full Version : Intermittent video trouble

09-13-2008, 04:49 PM
Hi, gang,

I'm not sure whether this would be best posted here or under "Hardware," but here goes...

I've been having a weird problem with my own desktop computer for a couple of days. About 1 time in 3 when I first start up the machine, I'll get no video at all. Apparently the vid card itself just isn't initializing, or isn't putting out a signal. Windows starts otherwise normally, and I'm able to restart it "blind" using keyboard shortcuts. When I try settings on the monitor itself, I get a "no video signal detected" warning. It's an XP Home machine with an Nvidia FX5500 card, several years old for both. The only change I've made video-wise is a new monitor (warranty replacement Viewsonic VP2130b), but that was installed a couple months ago. I've checked the event logs and nothing shows up. Could this be a sign of the CMOS battery on its last legs, and somehow the system is attempting to initialize the default onboard video rather than the AGP?

This is like one of those maddening trips to the mechanic when you say "well, it was doing it a while ago." Thanks in advance for any ideas.


09-13-2008, 10:58 PM
Can you see the post screen or anything after that, or is it just totally blank?

Since you have an add-on card and on-board video you should try switching over a couple days and see if it still happens. You can at least rule out your video card.

09-14-2008, 12:19 AM
One other thing, I had a similar system here... turned out (eventually) that it was the power supply. Don't know why, all voltages tested within limits but replacing the p/s made the problem disappear.

Another thing, is it connected straight to a monitor or is there a KVM involved?

09-14-2008, 04:16 PM
Thanks for the replies, guys, and apologies for the poorly-written post. As I was writing I got a panicked call from my sister whose computer refused to boot up at all, so I had to hit the road. It turns out that her power supply had bought the farm, and I was able to swap out the cheap replacement from my toolkit until a new one arrives in the mail. I was hoping for some things to try after I handled the emergency, and that's what I got - thanks!

I'll try each of the suggestions, one at a time. It's not a heat issue - hardly a speck of dust in my case, and all fans working fine.

The vid card seems to be seated fine, and I've re-seated it to make sure. The monitor is attached directly to the video card (I'll also try the VGA output, rather than the DVI to rule that out).

I'll re-enable the onboard video, and see how that works - good idea!

As for the power supply, I loaned out my test unit, so I can't do a swap, but I have a power supply tester in my kit (I plan to have a couple of new units in my field kit when I open my doors for business in a couple weeks). I hope it works, because of the 3 PSs I've tested with it so far, I was only able to connect the 20/24 pin connector from one of them; the fitting on the tester is so darned tight that I was unable to insert the connectors on the other two PSs far enough to make good contact. It's a new Coolmax PS-224 tester. I'm no weakling, but it was just about impossible, and my fingers were raw when I finally gave up.

Thanks again!

09-14-2008, 07:33 PM
Thanks, that's really useful.

09-16-2008, 03:24 AM
Thanks for the suggestions, all. I haven't dug into it yet, however - a relative gave me a nice gift yesterday, an old Dell server, and I've been cleaning it up and reloading everything since. It should be a great educational tool for me, if nothing else, since I have little experience with servers, and would like to acquire business owner clients eventually.

I'll post again when I have a chance to look into my own desktop again.