I've tried installing a new GeForce FX 5200 PCI card (not PCI-E) into my XP computer that previously only had motherboard on-board graphics capability. I have installed all relevant software and disabled the old graphics adapter through Device Manager > Display Devices. The computer appears to be recognising the graphics card just fine, however when I try plugging the monitor into the graphics card and turning the computer on a monitor message appears saying "Mode not supported - H:45KHz V:85.7Hz". So I'm guessing that the graphics card has defaulted to an 85Hz refresh rate, which my monitor doesn't support. The strange thing is that even after disabling the original graphics adapter, I can still plug the monitor into the old socket and it continues to work, though only on the lowest resolution and colour depth. Also, if I check Display > Properties > Settings, it shows as though I have a dual monitor setup, though indicates that one of the monitors is unplugged. I've tried going into the graphics card settings and changing the refresh rate down (I've checked the setup through the original graphics adapter and it was True Colour, 1152x864, 75Hz), but it doesn't seem to make any difference, and in fact half the time when I go back to the settings to check them they have automatically reverted to the 85 Hz refresh rate. What else can I do?

I would start over from scratch. Re-enable the onboard graphics in Device Manager, uninstall the nvidia drivers, then shutdown & remove the FX5200. Connect the monitor to the onboard port, boot back into Windows & uninstall the drivers for the onboard, then shutdown again. Re-install the FX5200 & connect the monitor to it. Boot the system & immediately enter the BIOS. Look for settings related to the onboard graphics & disable them...there may be a simple Enable/Disable setting or a setting for "shared memory" (set it to 'none"). Also look for an "Initial Display First" setting & change it to PCI. Save your settings & exit. Boot into Windows, let it detect the new card & install generic drivers. Once that's done, pop in the drivers disc that came with the card & install the nVidia drivers. Or you can download the latest & greatest from the nVidia site: http://www.nvidia.com/object/winxp_...

Thanks for that! It's working now - I think it was the BIOS thing that was the key. I had actually tried that before but for some reason it caused BOTH graphics adapters to fail (I had to remove the motherboard battery to reset the BIOS before I could see anything again). Only thing is... now the graphics card is working, it doesn't seem to have made any difference! In fact, it seems even *slower* than with the on-board graphics adapter. Is this possible/likely?