That youtube link Arkaige posted was a good one.
Its a slower CPU than OP, with same GPU, and he plays around with Doom until he gets 60+ fps and game looking as good as it can on his system.
There are still area's where its so demanding on his cpu it drops down to 35-40 fps ranges, but its def. playable.
So OP, you need to buy a stick of 8gb memory and put in your system.
You need to use tuneing tools to give your gpu a slight OC, and then you need to play Doom 720p, and play around with the settings until your statisfied with the way it runs.







