afaik 4-4-4-12 @ 900 could possibly be a problem, but someone with ddr2 experience will have to clear that up. Putting more volts on your NB means that you can raise the FSB higher, which in turn increases you CPU clock. So you may have to increase it to get to a 3.2ghz, as well as increasing the CPU volts.
I would def recommend getting a new cooler tho if ur planning to run it @ 3.2ghz 24/7, even a cheap Arctic Cooling cooler would be miles better than the stock cooler.
DFI LP X48 LT T2R | Bios 12/24 | XSPC Delta Chipset
Intel Q9550 E0 @ 3.6ghz (424 x 8.5) | Swiftech GTZ
OCZ PC2-9200 4GB (2 x 2G
Flex II @ 1121mhz 5-5-5-15 2T
2 x Sapphire 4870 1GB @ 780/4000
Auzentech Forte 7.1
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Enermax Modu82+ 625W
Custom Water Cooling
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