I'm building a computer for gaming, and trying to decide on whether to use Raid 5, with 3 drives, or Raid 10 with 4 drives.
Cost isn't a huge issue for me, and Raid 5 is more than redundant enough for me, so don't care about the extra redundancy. I'm just curious will a 4 drive Raid 10 have much of a performance increase for reading/writing over a 3 drive Raid 5?
With HDD being so cheap these days, for a boot/system drive RAID10 would be much more ideal.
RAID5 is used when minimal capacity sacrifice is needed for redundancy due to cost e.g. a large 8 drive storage/archive array. RAID5 also comes with severe write performance penalty if no write-back cache is used or when used needs either a BBU (from controller card) or a UPS in the case of power failure. Not the most ideal form redundancy for average desktop usage.
I second wruzy with his preference for raid 10 if performance is main concern, especially random writes. But by the time you have purchased 4 drives you have spent about $300 or so depending on what size drives you bought. The same money gets you an SSD which will get your load times noticeably faster than a disk RAID. After your game is loaded the drive performance will be not noticed. If you need space for media pick up a few large and cheap 5400 rpm drives and mirror them. Its just another way to think about solving your problem.