I don't know why they're so expensive right now (should be $150-160) but I'm working on getting these OCZ Platinum Rev 2s up to 500MHz (DDR2-1000) 5-5-5-15 stable. 490 is completely doable at max EVP 2.2V, 560 can run Memtest at 2.4V but gets errors (have to work on subtimings/settings). Hell even 580 POSTs and runs Memtest but that maxes out my CPU so no 300 . Which is weird since the last set I had did not respond to voltage at all, and crapped out at 460 @ 2.1V.