Graphics card for Dell dimension E521

[Verimark]

I've had this computer for a while now mainly just playing Counter Strike: Source, but i want to be able to play Call of Duty:World at War and other games that require a better graphics than what i have, but I've no idea where to look, I don't want to spend a huge amount as well.

Specs
AMD Athlon 64 Processor 3800+
2.4 Gz
Dx level 9
1GB of RAM
Radeon X1300 graphics card

Thanks.

[nunyadam]

Dell Dimension E521 Product Details

this should be his current specs.

[KarmaKiller]

So what do you mean by "huge amount"
You have a PCI-e slot (thanks nunya) so really all you'll need is a new power supply, and then the new GPU.
For the power supply, I would get this:
Newegg.com - SILVERSTONE ST400 400W ATX 12V 2.2 Power Supply - Power Supplies

Then depending on your budget, one of these: (in order from slowest to fastest)
Newegg.com - XFX PVT96OSDFH GeForce 9600 GSO 768MB 192-bit GDDR2 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Desktop Graphics / Video Cards
or
Newegg.com - MSI N9600GT 512M OC GeForce 9600 GT 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Desktop Graphics / Video Cards
or
Newegg.com - EVGA 512-P3-N971-TR GeForce 9800 GT 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Desktop Graphics / Video Cards
or
Newegg.com - BFG Tech BFGE98512GTXOCE GeForce 9800 GTX 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Desktop Graphics / Video Cards