First of all, this is my spec :
- Radeon HD6850
- 2x4Go DDR3
- Gigabyte H61M-D2-B3
- Intel Core I5 2400 @ 3.10Ghz 3.30Ghz
I plan to buy a GTX660, here are my questions :
- Will my CPU bottleneck my new graphic card?
- Will I notice a big difference in game such as Battlefield 3 ?
- I want to upgrade the rest of my computer later this year, what are your recommandations ?
You should be fine. The CPU is plenty for the GPU you have suggested. HERE is the different performance you might get (obviously your not using the same CPU than in the comparison, but should give you an idea).
I'm terribly sorry but I don't quite remember about my PSU as it has been a year since I bought the computer and I don't have the papers here.
As far as I can remember, it has to be a 650W but I can't tell you more precisly.
Anyways, this is not the most expensive part, so if you tell me 650W isn't enough, I could still change it with the GPU.
Assuming you have a quality PSU you should be fine. Hopefully you got an Antec, Corsair, Seasonic, PCP&C, & XFX are all good quality PSU's. I usually look up my parts that I ordered online, if I don't know them, but that is just me.