My current system: Asus P6T Deluxe GTX470 heavily overclocked (higher voltage) i7920 @ 4ghz (less than stock volts) 2 x 2TB Samsung Spin Points DVD Writer 6GB DDR3 XMS3 @ XMP Corsair HX520 The above setup has been perfectly stable for months under any circumstances (can't remember the last crash). 520watt PSU might seem small given today's massive PSU's, but the original HX line were immense PSU's and could handle a hell of a lot, not to mention most big PSU's are just plain overkill. Now today I added another 6GB of memory (12GB total), although this isn't an exact match (Patriot Viper) it does match stats-wise and both sets run on the same XMP profile. Since adding in this ram I've experienced 2 system lockups - the screen freezes like a screenshot and nothing moves, crt-alt-delete doesn't work, and a hard reset is necessary. My first thought was the ram - but 4 passes of memtest later and it's fine! So I'm wondering if I've finally overloaded my psu? Anyway to tell?