GPU upgrade for a friends system

[LukieBoy007]

Hi,
My friend is looking to upgrade his system, and the best bet is a new GPU.
This is his current system, which is about 8 months old:
A10-5800k
Gigabyte FM2 A85X Motherboard
8GB RAM
Windows 7 x64

He currently games using the onboard graphics, which is sufficient but he is looking for an upgrade. What would be the best upgrade? Don't really want to go over £120, secondhand doesn't matter but he would definitely prefer it if it wasn't.

Thanks!

 

[LukieBoy007]

Thanks for the replies, I'll pass all this on to him. He's interested in overclocking the CPU if required, so that will probably be done too.
Thanks