Bought this to power my Crossfire system. 2 x XFX HD Radeons 5870s. I already was using a XFX 650w PSU in this system and it works perfect but my 2nd PC was in need of a new PSU so decided to get this OCZ 750w and put the 650w in the 2nd PC. Completely modular, yes it is, no attached cables at all, excellent for managing cables. So I installed it and powered it up. First impressions was it's a bit louder than the XFX but not a big problem. As with most modern, brand name, PSUs as the load on the PSU increases like when you're gaming the fan will increase in speed to cool the PSU. I started Unigine's Heaven Benchmark to put the system through its paces. As benchmark continued I heard my graphic card fans speed up, they are very quiet Artic Turbo Coolers, even at 100% RPM they are barely audible and the PSU remained at the same noise level. As the benchmark neared the end (most stressful time for the system) the PSU's fan suddenly kicked in with a `WHOOSH!' and maxed out its fan speed. Very, very noisy. I quit the benchmark and waited for the PSU to cool and the fan to slow down - it didn't. After 10 minutes still the very loud noise of the fan even though my graphic cards had cooled to 28c and were on minimum load. Only a restart cured the excessive fan speed. Tried a game, Skyrim, PSU's fan lasted 3 minutes into the game at its lowest RPM before `taking off'. Believe me this PSU is loud at full load. So out with the OCZ and back to the practical silence of the XFX.
Bad buy, avoid.