Krysset wrote:
Oh okey, well I've had bad fps since I bought the computer..
Sorry to say that your graphics card sucks balls

take a look
here - the 2400XT is something like 20% faster than your 'non-XT' card, and even the XT struggles here (in ancient games, at crappy low resolutions).
Your motherboard is fine, it'll take any modern graphics card. The limiting factors will be:
1) Does it fit in your case
2) Can your power supply handle it.
The links you've posted don't give me any info about your power supply. You'll have to crack open the case and take a look but the things to check are how many watts it can provide, and also check if it has any PCI-E power connectors. These are the sort of cards you should be aiming for:
350-430W Power supply, no PCI-E connectors - Nvidia GT220
350-430W Power supply, with PCI-E connector - Radeon 4650/4670 or Nvidia GT240
430W+ Power supply, with PCI-E connector - Radeon 5570/5670
Go for the highest model number you have the power supply for. The £65 5670 is SIX TIMES more powerful than the £35 4350, so buying the low-end cards to save money is not clever!