Well 6gb of ram is a strange number for a dual-channel cpu like the i5-2320 (you are using 2x2gb and 2x1gb then?). Mismatched ram can cause problems. I try to keep things simple and buy ram in matched kits (like 2 x 4gb or 4 x 2gb to give you 8gb). As far as the PSU goes, if its a >=350w Dell (probably made by Delta) then in theory it should work fine for your system, but you've mentioned crashing and other problems. The Corsair CX430 is a decent PSU within its class and price range and should work fine for you. If you want peace of mind, then upgrade your current PSU. And use that ram in matched multiples of 2 to maintain dual-channel.