You should be careful when buying a graphics card. If your computer is only a 300Mhz, then you can't just go out, and buy the best one you can find. It most likley won't work on your computer.
First of all, look for one that is AGP- this only applies of course, if your computer has an AGP slot. Check this before you buy.
Just make sure you check the system requirements of the card before you buy it, and remember that some places don't do returns on computer equip. once it has been opened.
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