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M4A78 pro OC (DDR2 RAM help please)

2038 Views 1 Reply 2 Participants Last post by  Mashur
hi, i ve got the following, M4A78 pro motherboard, AMD phenom 2 940 BE OC to 3.8 ghz, and 8 gb ram (4 x2) 1066 kingston hyper X DDR2 8500. i am trying to configure my ddr2 to its normal frequency at 1066 but in my bios and cpuz it states that am running at 800 mhz. i ve tryed changing that manually to 1066 and raising the volts to 2.35 max, i ve also tried lower. i ve not wanted to try higher as it will probably burn them. because i have a Black edition CPU i ve used multiplier to oc not FSB. 200 x 19 = 3800 at 1.52 v but now why doesnt my ram go to its default frequency of 1066 no matter what i do? am i missing something? its in unganged mode a 2T with 5-5-5-18, i ve tried to change that to 5-5-5-15 on dect 0 and dect 1 (whatever that is) what am i doing wrong? should i try overclocking my fsb to 266 to get the ram that i paid for without even overclocking? someone please help.

ps. also running an HD 4980 with 600W psu 3 HDD and a sat card. could it be my psu that can't handle that? otherwise i ll downclock my cpu to 3.6 or even lower if that means i can use my ram for its value
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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.
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