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#11
Im assuming youve done the basics already, all drivers up to date, chipset etc?
Have you tested for stablitiy with all the DIMMS full?
Possibly why it seems slower, if not completely stable.
You may need to underclock the RAM slightly to get stable with all 4 slots full , or increase NB voltages to compensate for the additional load..
All boards are different, and react differently.
When the say its rated for X speed up to X amount of RAM, doesn't always mean it can do both at the same time.
It depends on the board itself.
May also want to check the Man. site, to see if theres a critical bios update relating to RAM
And as computersplus suggested, set the voltage to whatever the RAM is rated for at its MAX side.
overclocking will be much more difficult with all slots full as well.