Graphics card upgrade

Sorry this isn't about my mac it's about my PC
i'm wanting to upgrade my current graphics card (ATI Radeon X600 PRO) to a new one preferably DX10. Not wanting to spend over ~£80 max ~£100 can anyone suggest some good graphics cards for me

for that price you can go with something like ATI Radeon 3870 which is at its lowest specs around a 100 pounds or the 3850 which you can get right in the middle of that price range

they're not the newest things in town, but still decent .. don't know about nvidia .... strange considering i have nvidia in my macbook but ati will cost you less and the performance is not all that worse (the 4870 is probably the best card out there imo)

I'm not so sure with british pricing, so I just did a quick google to get in the price range

Best cheap video card for the money right now is the Radeon HD4830, hands down. It's on par with the 3870 and draws less power. Not sure on prices, but in the U.S. it seems as though the 4830 costs the same or even less than the 3870 (which has been discontinued).

Here we go: PowerColor HD 4830 512MB GDDR3 DVI VGA HDMI PCI-E Graphics Card - Ebuyer

Ebuyer looks pretty good.

With graphics cards will they always fit in with the motherboard ? don't want to buy one then find out it doesn't work

That depends. Does your motherboard have PCI Express or AGP? If it uses PCIe, it'll work. If it uses AGP, then it won't and you'll have to look for a good AGP video card. Those are getting hard to find these days - I think the best AGP card is the Radeon HD3850, but it might be kind of expensive. If you do have AGP and you can't afford a 3850, look for an AGP Radeon 2600XT instead.