Verified answer

That machine is too old to support anything above entry-level cards.

With a Pentium D processor at best (and possibly a single-core Pentium 4) your CPU will just be a bottleneck for any midrange graphic cards. You've also got a 310W power supply which might be on it's last legs- power supplies get weaker over time due to capacitor aging. Finally, the PCI-E x16 slot is almost certainly version 1.0.

So your best choice is probably a GeForce GT 440 (or the GT 630, which is the same thing rebadged). Next-best would be the GT 430 (the GT 620 is that same card rebadged)

Your power supply doesn't provide the 6-pin connector required by faster cards like the GTS 450 and GTX 550 Ti. Since you have brand-name computer with an original PCI-E x16 slot (version 1.0) you'll want to stick to version 2.0 PCI-E x16 cards. Some OEM motherboards of that vintage are incompatible with version 2.1 cards. So the Radeon HD 6570 and 6670 might not work... if you're willing to try them, they are faster than the Nvidia cards listed above.

Arnak is basically right, he just made a typo. He meant version 2 PCI-E x16 slot, not PCI-E x2 slot.

Hi,

That motherboard has a PCIe x 16 expansion slot but I can't find out which version.8-((

Possibly version 1 or 1.1 which will limit your choice of cards but you need to check with Lenovo to be sure.

Ideally you need a PCIe x 2 slot.

Depending on the card you will most likely have to upgrade your power supply as well.

Arnak