i see this from time to time with the custom motherboards such as asrock. this is one of those instances where the auto-tune function in BIOS may need to be set manually. Standard DDR2 voltage should be around 1.8v and i think you can increase voltage by small increments. i myself have tuned DDR2 up to 1.95v and tested the RAM to Bleep and back with no adverse results, but it is best to increase the voltage in the smallest increments available at a time to check. DRAM Power should be available in your BIOS, and probably defaults to "Auto". Most of the time, leaving the ram power set at Auto is going to work well, but there are exceptions, typically seen on the older custom mobos like yours.
one more thing, there very well could be an exception pertaining to a BIOS update. i have seen BIOS updates address these kinds of concerns (support for hardware that supercedes the release date of the mobo itself)
here is the page for that mobo and the BIOS editions, looks like the descriptions for the root cause of the updates are not very detailed, but that is typical.
and here on this support/download page i see some non-descript RAM concerns being addresed back in 12-2008.
Edited by synergy513, 12 September 2016 - 08:25 PM.