use something like CPU-Z or WCPU-ID to find out what the ram's reported
SPD settings are - these SHOULD be what the mobo wants to set them at by
default. The SPD values may not match the given spec, but the ram should
work at the given spec if you manually set it there. Bump voltage 0.1
volt up if a memtest86+ fails. If still no good at stated spec then send
'em back and get another brand.

are there any other sticks in there? the mobo will need to set a speed
that is compat w/ all sticks.

ALWAYS ALWAYS ALWAYS do a memtest to validate new ram BEFORE booting into
any OS on the HD - boot from floppy and make sure it passes! Booting to an
OS has the potential to corrupt the HD (HD data buffers are stored in RAM
prior to writting, so if ram is bad data written to disk can be bad too.)
NEVER install an OS to HD if ram is not 100% perfect!