well i have a m4a78 pro motherboard. I've researched all i could on it
basically what is happening to your memory is that it is being down clocked due to the use of all 4 ddr2 slots
here are the different configurations for your memory
yellow slots
black slots
when you put memory in one yellow slot it works as single channel at speed of memory
if you add a another memory to the yellow slot it works as dual channel
same with the black
If you put a memory in one yellow and one in the matching black you get 2 single channel memory at memory speeds
once you put 4 memory chips in. the motherboard down clocks to 800mhz. since now you have a setup called 2x dual channel
the motherboard has to divide up the bandwith and frequencies to allow to run all 4 slots at the same time. You'll only get full speed if you stick with 2 sticks of ram only. going with either 2x 2gb or 2x 4gb.
basically what is happening to your memory is that it is being down clocked due to the use of all 4 ddr2 slots
here are the different configurations for your memory
yellow slots
black slots
when you put memory in one yellow slot it works as single channel at speed of memory
if you add a another memory to the yellow slot it works as dual channel
same with the black
If you put a memory in one yellow and one in the matching black you get 2 single channel memory at memory speeds
once you put 4 memory chips in. the motherboard down clocks to 800mhz. since now you have a setup called 2x dual channel
the motherboard has to divide up the bandwith and frequencies to allow to run all 4 slots at the same time. You'll only get full speed if you stick with 2 sticks of ram only. going with either 2x 2gb or 2x 4gb.
