I recently had my hard drive fail on my alienware x51. I'm looking at getting a samsung evo either 250gb or 500 gb. Im not sure what size i should get, i will be using it to run the operating system and maybe a few games. My other drive which I will also have along with the sad is a Western Digital WD10EZEX 1TB. Im not sure if i should get the black WD though? I pretty much use my pc for gaming and financial excel workbooks. Any advice?