The maximum that I have seen on my 280x and 7970 was 250 h/s. How can I get 290 h/s? Do a modified BIOS provides significant increase?

on stock bios max is 260H/s on 7970 and 280x. If you want to near 290H/s from tahiti, hack bios, but don't forget to make a backup Wink

my stock 280x was like 245
strapped 280x i get like 266
is it because elpida memory ?
running at 1020 clock and 1500 memory

Yes, elpida memory little slower then hynix AFR. All my card have hynix AFR, and i don't now how to optimize elpida Huh

i'm running 1100/1575 and 1100/1500 are close to max H/s too