So I currently have an AMD Athlon II X2 270 CPU that takes 65W and a 1GB AMD Radeon HD 6670 GPU (Couldn't Find Watts) on an ASRock A785GM-LE Motherboard with 2 1GB Dual-Channel DDR2 DIMM Ram Sticks with a 186GB Seagate ST3200826A HDD and want to upgrade to a faster CPU, GPU, and RAM. I've found some 4GB RAM kits and my friend recommended an AMD Phenom II X4(Just that, no 850 or anything) and a compatible GPU(he didn't tell me what). My power supply isn't really marked, but seems to be a Cooler Master RS-500-PCAR-D3. Most sites say it's 500W and I don't want to have to buy a new Power supply if I don't need to. What would be a good upgrade? I want to be able to play Overwatch without much lag, so I guess consider that the minimun? Also, my case is small(the PC was custom built by that friend), but I don't know the ACTUAL measurements. Also, if I just got another of the same HDD, would it extend the C: Drive? Because I don't want to lose my memory.