Upgrading Radeon X1650SE on old system

[Useless_98]

APPROXIMATE PURCHASE DATE: ASAP
BUDGET RANGE: up to £120ish (~$180)

USAGE FROM MOST TO LEAST IMPORTANT: Gaming (Dragon Age, Mass Effect and sequels, Fallout etc)

CURRENT GPU AND POWER SUPPLY: ATI Radeon X1650SE and Corsair 620W PSU

OTHER RELEVANT SYSTEM SPECS:
2.3ghz Intel Core 2 Duo
4 gig DDR2 RAM
ASUSTek Computer INC. LEONITE 5.00 Mobo (aka P5LP-LE) w/ 1 x PCIe 1.0 slot.
Windows Vista 32bit SP2

PREFERRED WEBSITE(S) FOR PARTS:
No preference, but must be UK based or ship to UK at favourable rates.

PARTS PREFERENCES: None

OVERCLOCKING: No SLI OR CROSSFIRE: No

MONITOR RESOLUTION: (e.g.: 1024x768, 1280x1024+)

ADDITIONAL COMMENTS: Basically I'm looking for the best card my ageing system can efficiently use. Recently I bought a Radeon HD 5750 and even though I had a PCI E slot, my crappy HP mobo didn't have a recent enough BIOS update to run it. Now I'm stuck with just an upgraded PSU.

Although I know my system is starting to get near retirement age, ideally I'd like something that will give good performance on the above games and still allow me to run newer releases on pared down settings.

After my failure with the 5750, I don't really know where to start looking, but fI guess something like this would work? Radeon HD 4850 512 MB http://www.tomshardware.com/reviews/gaming-radeon-hd-geforce-gtx,2676-3.html

Any help much appreciated.

 

[rolli59]

Hd4850 or GTS250 are going to give you performance on level with HD5750 and go well with your CPU.

 

[Useless_98]

Great, I was hoping it would be that easy .

Thanks for the help.