Do the following

1.) Connect 1 Graphics Card to the PC
2.) WINATIFlash Download Current Bios from Card
3.) Open Bios with Polaris Editor
4.) Copy the 1500 Memory Timing and Paste it in every slot above it, 1625, 1750, 2000
5.) Save Bios
6.) Flash Bios to Card with WINATIFlash