GPU advice

O helo /tech/ I'm shopping for a new low-mid tier GPU, no more than £100 max but ideally I'd like to go cheaper because I'm poor.

I currently have a Geforce GT 440 which is giving me BSODs and keeps not being detected by BIOS. It's old and not great and I'd rather not dick around and just get a new GPU.

My whole machine is pretty low tier, I'm running an AMD FX-4100 quad @3.6ghz, 8gb/ram and a 500w PSU.

Any help would be greatly appreciated, or pointing me in the right direction at least.

Thanks /tech/

Have a look at online auctions for cheaper parts. I work at one and we often sell gpus at like a third of the full price. We sell like 7850's for less than 100. Something like a 680 goes for over 200£