since they are what controls the resolution.
Have you been to Control Panel, System, Hardware tab, and clicked the Device Manager button. Open the Monitor(s), then double click your monitor. Try the "Update. . ." function. Have XP go to the 'net and look for updated drivers.
I have 2 monitors, each connected to a seperate graphics card. My first monitor, 19" LCD MAG Innovision Tco03, connected to a nVidia GForce 4 MX 440 Graphics card, has just today, lost its 'life' and no longer displays proper results. Screen resolution has gone down from 1280x1024 to 640x480, and both screens now display MAINLY 4bit colors (the functional one displays some good color within MSN).
I have tried to change the display back, but I have been unsuccessful, I would like to view what options could be causing this. Within the next few days, I will be trying to reinstall the driver, along with securing that it is properly connected into the slot on the PCI board.
I will be needing full detailed instructions (but suitably brief and to the point to avoid confusion) and I will probably need online support for this (my MSN is th_throstur@hotmail.com in case this is something you are capable of helping me with) and I hope that something can be done without reinstalling any drivers, since the risk of something happening is noticably high (nothing ever goes right for me, no sirree).
By the way, I am running a Windows XP (32bit) on a (partially) compressed 37.2 GB HDD, Intel Celeron 1.6949 GHz 256 MB RAM
+ I have already scanned the harddisk with AVG for viruses.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic