I am building a new computer and have a question about memory. The processor is a Q9550 and the mobo a Gigabyte GA-P45-UD3P which supports a FSB of up to 1600 MHz. I would like the processor and the memory to run in sync. If I overclock the Q9550 from 4x333MHz to 4x400 Mhz it will be maxed out on this mobo since it only supports chips up to 1600 MHz, yes? And for it to be running in sync with the memory I would want to 800 MHz Ram, yes? I was looking at the G Skill PI Black 900 MHz but then I realized... will I actually get any more out of it that memory? Would it be more efficient having 800 MHz running in sync? Anwyay, just don't want to buy the PI Black if I'm not going to get anything more out of it for the extra money.
Or if I did go with the PI Black would I have to get a different mobo that supports chips up to 1800 MHz. I have too many questions. Ahhhhh..
That motherboard have been proven able to run up to 533 *4 (2132 FSB). You should go ahead and plan on buying 1066mhz RAM, the price difference is sometimes less than $10, compared to 800mhz RAM. It will allow you to max overclock your processor without having to worry about RAM speed.
Hey there prophet. Just because it says that it supports 1600Mhz doesn't mean that it won't go over or that you have to run it at 1600MHz. It means that it will run a CPU that is default 400Mhz like a QX9770.
Your FSB should default to your CPU specs which will be 333Mhz.
So getting to your RAM. There is a multiplier on your RAM that you can use. Normally it is set to 1:1 ratio with the FSB. So if you are running at 333Mhz FSB, your RAM will be set to 667Mhz with a 1:1 ratio. You can change that ratio and bump your RAM frequencies up without bumping up your FSB. Otherwise it would be pretty impossible to use DDR2 1066 at that speed since you would have to put your FSB up to 533Mhz. Make sense?
I have DDR2 800 and I am running with a certain ratio that I am not sure of at the moment but works out to somewhere around 1000Mhz with a FSB of 430. You can get DDR2 800 and it will OC along with any FSB that you can throw at it with a 1:1 ratio. Usually your CPU will crap out before your RAM does. If you want to run your RAM at higher frequencies then look into DDR2 1066. I wouldn't bother with 900 unless it is the same price as 800.
Actually, this completely slipped my mind but you can reduce your CPU multiplier and up your FSB ....for example do 500 x 6 to get a 3Ghz CPU OC and to run your RAM with a 1:1 ratio at 1000Mhz....but you can only get so high of a FSB since you have to start messing with your north bridge voltages and temps.
Anyway, there is a lot of this 1:1 taboo floating around and it has been around for a long time. I have no clue if it is true or not. It seems like there are so many different combinations of mobos-RAM modules-Frequencies-FSB-latencies that there is no definite answer. I haven't had stability issues running on a ratio other than 1:1 but I also haven't benched it out on my system to see if it matters.