what speed RAM for QX9650

tipoo

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hey everyone, a friend of mine is building a high-end comp with a QX9650 processor in it, but we are both kind of confused as to what speed RAM we should get for it... from what i can understand, the fsb of the processor is 1333MHZ, and the closest clocked RAM we can find is pc2-9200 at 1150mhz. would it be pointless to get this ram? what speed should he get?

EDIT: by the way this is for some hardcore video editing.
 

homerdog

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KyleSTL

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Intel equipment sees the most improvements in synchronous modes (i.e. 1:1 and 1:2 FSB:Mem), so since the QX9650 is 333mhz quad-pumped FSB, that would mean 333mhz (DDR2 667) or 666mhz (DDR3 1333). DDR2 800 barely outperforms DDR2 667. The reason people are buying DDR2 800 is to overclock (with a 1:1) up to 400mhz bus (1600mhz FSB). However, that processor has an unlocked multiplier so raising the FSB is mearly optional to overclock. I would suggest going with DDR2 800 since it costs barely more than equivalent DDR2 667 and leaves you headroom if you wanna play around with OCing. Don't waste your money on anything above DDR2 800 since the gains are negligable and the cost is astronomical, unless you're planning on doing some hardcore crazy overclocks.
 

starcraftfanatic

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get 2x2GB of 800Mhz DDR2. The huge cache of Core 2's makes the gain in RAM speeds above a certain point (around 700Mhz) decline exponentially (like the last $60-80 million in the Yankees salary). Search newegg for some cheap models from good brands. Lower latency is a bigger factor than more clock cycles.
 

imrul

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to know what ram to get, divide the FSB by half, so 1333/2= DDR2 667
if you plan to overclock by the FSB then get DDR2 800.
you can also overclock by the multiplier, this means you wont hav to use ddr2 800 and just use ddr2 667 to overclock
 

homerdog

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The price difference between DDR2-667 and DDR2-800 is minimal, and DDR2-800 is slightly faster despite it not running 1:2. imrul is right in saying that DDR2-667 is good enough, but there is no real reason not to get DDR2-800.
 

tipoo

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ok so 2x2gb of 800mhz RAM it is... i will tell him to shop around for something cheaper.

oh, and what are good timings for this memory?
 

KyleSTL

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5-5-5-15
or
4-4-4-12

Don't go for the quicker modules. Intel architecture doesn't translate the faster timings well into real-world performance because of the mem controller being located on the NB.