Hello, I think my CPU is bottlenecking the GPU because the usage never goes above 50% when I am playing games and that causes lag. So if it's from the CPU how high can I overclock it and will the bottlenecking stop ?
CPU: AMD Athlon 64 X2 Dual Core 4200+ 2.20 GHZ
GPU: Nvidia GeForce GT 440 1GB GDDR5
I wouldn't recommend buying anything less than a GTX460 in the nVidia line as even that card is aged and pretty much phased out. Now that comparison isn't true life results or anything; but it does give you a good idea.
You're GPU is probably the weakest link paired with that X2. The best idea I have for you is to upgrade to a GTX550Ti or better card. I hope this helps as I don't believe overclocking that CPU is going to do any good for you.