I turned on my computer tonight and there were streaks/lines in my monitor. At first I thought my monitor cables were loose so I loosened it and replugged it in. I also restarted the system but to no avail. I did try opening up the computer and reseating the graphics card but it didn't do any good. I also plugged the monitor to another computer and it was fine. Since the monitor itself is fine, could it be possible it's a virus? Or faulty graphics card?

LCD or CRT?

Are the streaks certain colors, or just black? Do they run horizontal or vertical?

First thing I'd try is using a different cable and making sure both plugs are plugged in securely and not damaged.

Sounds to me like the and issue with the video card. I had a similar issue on one of my own systems. The vga port came loose over time and I got lines, streaks and some funky shading. Do the lines appear when the system is first powered on, or when it boots to the OS?

It's an LCD with green vertical streaks.

When it powers on from the Windows XP splash screen all the way to booting into the OS, I notice vertical streaks from various parts in the monitor. I tried changing from the DVI cable to an analog cable, in hopes that the DVI input was faulty, but looks like both are at this point.

I'll try and get a picture, if possible. TIA.

EDIT: Now looks like it's red or blue vertical streaks on my monitor.

Got another computer or laptop you can hook into this monitor to verify it's not the monitor itself? Looks like you've already tried different cables.

Sounds like the video card to me as well. You could always try reloading the video drivers, but it is doubtful if that will do anything for you. When you connected it to your other PC, I assume you used the same cable?

I had a video card that suddenly went bad after running one of those giveaway of the day games. Upgrading the driver did seem to help in that case, but I still chose to get a replacement since it was under warranty.

I tried plugging the monitor to another system and the monitor was fine. At first I thought it was a virus of some sort that manipulated the graphics driver settings, since it happened after plugging my USB drive to move some files to my system.

I thought it was a bad DVI cable, so I went back to analog, and it was fine at first, but the monitor was the same after loading up. I checked the cables to see if it was messed up, but it looked ok.

I'll go with the updating drivers route first to see if that solves it. Otherwise, I have a backup graphics card here at work I can use to see if it solves the problem. Would I need to uninstall the video card drivers before installing the new one? Thanks all for the suggestions.

To avoid any headaches, yes I would uninstall your existing drivers. Just rollback to the default VGA driver prior to shutting down to swap video cards. Windows is usually pretty good about detecting video card changes, but I have seen instances where the initial boot didn't work and you had to restart in VGA mode in order to uninstall the old and install the new drivers.

One more thing...is there some type of video card diagnostics I can run to see if the video card is indeed the culprit? Thanks.

I suppose it could be bad ram, if the video card uses shared memory.

The best diagnostic is your eyeballs. You tried the monitor on a different machine and worked fine. I also suggest trying a different monitor on this machine and seeing how it looks.

The easiest option if you have an extra system is to test the video card in another computer. That should give you a pretty definitive answer if the problem carries over.

I'm guessing you already tried a different monitor?

Yes.

What make/model video card is in the computer and does the motherboard have onboard grahics?

You probably have an ATI or nVidia card. If the control panel for either is installed, uninstall it, then go into device manager and uninstall the card (right click on the graphics card and choose uninstall), then shut down the PC and remove the video card. If you have a replacement video card, install it. Otherwise you can connect the monitor to the onboard graphics (if present).

After connecting the monitor to a new video source don't be surprised to see 640x480 or 800x600 resolution until the video drivers are installed.

Tried a different monitor and it did the same to the other monitor(lines/streaks). So video card looks like it's the culprit.



Since it's a AGP graphics card, the other 2 computers I have @ home only have PCI-E slots, I'll take the card to work to test it on a vacant machine.


I never really noticed it, but I'm pretty sure my mobo does have onboard graphics. When I picked up the machine from Dell a couple of years ago, it came installed with the ATI card and I never changed it. It did quite well playing first person shooter games like Painkiller, Far Cry, etc...

Thanks for walking me through the uninstallation process. The problematic card was the ATI Radeon 9800 AGP series card and I replaced it with a Nvidia GeForce4 Ti 4600 card.

After installing the new graphics card, it did in fact defaulted to 800x600 resolution and I used Nvidia's Automatically find drivers for my NVIDIA products option online to find the appropriate drivers. Now all looks well. Thanks all for helping!