You need to uninstall the drivers for the old graphics, then download and install new drivers for the card.

Whereabouts would I find the old drivers?

Either in add/remove programs or in the Device Manager.

Ok so I've had the card up and running for maybe a week. And these last few days I've started to get the same problems during bootup that I used to get before I installed the card. I'm very close to throwing my computer off a building.

Go to system properties (right click MyComputer > properties) > Advanced tab > under startup and recovery click settings > under System failure make sure "Write an event to the system log" is checked AND that "Automatically restart" is UNchecked. Then under *write debugging info* select (none) > Click "OK" and reboot.

If you crash again, write down the entire STOP message.
You can post it here for help and/or check it at this resource.
http://aumha.org/win5/kbestop.htm

Ok I went to that site but I'm kind of confused as to the advice they give me.
http://msdn.microsoft.com/en-gb/library/ms794023.aspx

Maybe you could help me translate that into terms I understand.

What was the full error message you received?

A problem has been detected and windows has shut down to prevent damage to your computer.

If this is the first time you have seen this stop error screen restart your computer. If this screen appears again follow these steps.

Check to see you have adequate disk space. If a driver is identified in the stop message, disable the driver or check with the manufacturer for driver updates. Try changing the video adapters.

Check with your vendor for any BIOS updates. Disable BIOS memory options such as caching or shadowing. If you need to use safe mode to remove or disable components, restart your computer, press F8 to select advanced options, and then select safe mode

Technical Information
Stop: 0x0000008E (0xC0000005, 0xBF801173, 0xBA736A48, 0x000000000)
Win 32K.sys - Address BF801173 base at BF800000 Date stamp 48ce4da7

Beginning dump of physical memory
Physical Memory Dump complete
Contact....

I cannot find anything at all regarding that particular error message .

You can try this if you wish;

Go to Start | Run and type in sfc /scannow and hit the Ok button. Insert your CD if/when requested.

I got this one today.
PAGE_FAULT_IN_NONPAGED_AREA

STOP 0x00000050 (0xC0AC331C, 0x00000000, 0x804E8D74, 0x00000002)