Looking to upgrade my system

[CapKaboom]

My current system consists of:

Power Supply ( 650 Watt -- Casegears ECO-Element 80 Plus Certificated High Efficiency Power Supply SLI Ready )
Processor ( Intel Core 2 Duo Processor E8500 (2x 3.16GHz/6MB L2 Cache/1333FSB) )
Processor Cooling ( Certified CPU Fan and Heatsink )
Motherboard ( Asus P5KPL-CM Intel G31 Chipset w/6-channels, Gb LAN, S-ATA 3Gb/s, USB 2.0, Single PCI-E MB )
Memory ( 4 GB [2 GB X2] DDR2-800 PC6400 Memory Module Corsair-Value or Major Brand )
Video Card ( ATI Radeon HD 4850 1GB PCI-Express x16 )
Video Card Brand ( Major Brand Powered by NVIDIA )
Hard Drive ( 500 GB HARD DRIVE [Serial-ATA-II, 3Gb, 7200 RPM, 16M Cache] )
2nd Hard Drive ( None )
Monitor ( LCD Monitor 22" Widescreen TFT LCD Monitor Support up to 1080P with HDCP [Black] )

I'm thinking I should upgrade my video card to one of the newer ones, but I'm not sure if my motherboard will require an upgrade as well to hold a bigger card. Can you guys recommend a newer video card to install, and a new motherboard if that's needed?

P.S. I'm running Windows XP SP3 at the moment. Do you think I should upgrade my OS to take advantage of the later DirectX versions?

Any help would be great, thank you all in advance.

 

[ScrewySqrl]

Casegears? I've never heard of that PSU brand, and would recommend replacing it with something of higher quality.

your overall system looks very much like mine (see my signature, below), and I'm preparing to replace it early next year with either a sandy bridge or a bulldozer build

 

[boiler1990]

You won't need to upgrade the mobo to get a new video card (assuming you're taking the old one out). Do you prefer ATI/AMD or NVIDIA?

The 6800 AMD series is pretty good, and the 6900s should come out this month (I think??).

I like NVIDIA's cards (also wanted the 3D stuff), and was happy with my SLIed GTX 460s and love my GTX 470s.

 

[geofelt]

What is your current problem? I assume it is FPS while gaming.
If so, what FPS are you getting now?
What do you want it to be?
Is the minimum FPS bothersome?

I think your system is relatively well balanced now, so both cpu and graphics upgrades may be in order.

It will make more sense to upgrade the graphics first because a new card can be carried over to a new cpu.

A 650w psu can normally run the strongest single video card out there.

Can you read the label and see how many amps the psu can deliver on the +12v rails in total?

If you just have some Christmas cash coming, I suggest you consider a SSD. It will make your PC feel much snappier, and it can also be carried forward to a new build.

I think windows-7 is a good OS. Just don't expect any magical performance increase. It will provide trim support for a SSD.
If you are a student, look into an academic license for about $30.