Need Help in Deciding Between DDR2 and DDR3

jaydub868

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Oct 14, 2007
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I'm trying to decide whether I should go DDR2 or DDR3 for my next build. For purposes of this discussion, cost is NOT as issue. Known components will be:
- Intel Q9550 quad-core CPU @ FSB 1333
- X48 Northbridge
- 4GB of either DDR2 CAS 4 or DDR3 CAS 7

I don't really intend to overclock, but I do want fast yet stable performance, and I figure you guys probably know more about this than most. My understanding is that Core 2 likes the memory to be in synch with the FSB. So, the two options are:
1. Go DDR2 and run the memory at DDR 667 (333x2) IN SYNCH with a FSB of 1333 (333x4).
2. Go DDR3 and run the memroy at DDR 1333 (667x2) or DDR 1600 (800x2) OUT OF SYNCH with a FSB of 1333 (333x4). This presumes that DDR3 can be run at 2x or 2.4x the speed of the FSB (is that possible?).

- Which option would provide better performance? Although DDR3 might appear to be the better choice, I'm not so sure given the FSB bottleneck and higher latency of DDR3.
- Is it possible to run DDR3 at 2x or 2.4x the speed of the FSB. If I go DDR3, I will be getting either a Asus P5E64 WS Evolution or a Gigabyte GAX48T-DQ6.

Thanks in advance for your time.
 

ausch30

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High-end DDR3 will give you a slight performance gain over DDR2 and the X48 chipset tends to like DDR3 more than DDR2 but in my opinion the difference isn't worth the price. Get some DDR2 800 and underclock it and tighten the timings to run 1:1 with the FSB and you will have a very fast system.
 

OS43

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I would get DDR2 for now. Make the switch when you get tri-channel DDR3 for a nehalem chipset sometime in the future.

No need to run the memory at 667. Why not just OC the CPU a "little" to 400?

Will this be a gaming PC? If so why not save a lot of money and OC an E8400 to a FSB of 425 or 450, and OC some good CAS4 DDR2 to DDR2 - 850 or 900.

Really no point getting the quad atm as far as I can tell, unless you do video editing or other heavily threaded apps.
 

jaydub868

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Thanks a lot for your help. Seems like DDR2 may be the way to go. Regarding the alternative:
- Do Gigabyte and Asus X48-based boards allow you to run DDR3 at double the FSB, i.e. if FSB=1333 (333x4), will BIOS allow me to set DDR3 frequency to 1333 (667x2)? How about DDR3 1600? I was thinking of either an Asus P5E64 WS Evolution or a Gigabyte GAX48T-DQ6.

- Given the bottleneck of the FSB, in what way would the higher bandwidth on the DDR3 still be beneficial?
 

doomturkey

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DDR3 does not actually perform any better than DDR2 atm, the timings suck too much. And since intel chips like to sync RAM and FSB, might as well get DDR2, 1:1 ratio, which gives DDR2 667, which means you can tighten timings all the way to CAS 3. OP said he has no intentions of OC, which is all DDR3 is good for atm.
 

cpt_bum

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Per my experience with both DDR2 and DDR3 chipsets I would prefer DDR3. Yeah it might cost more after all the upgrades however the overall experience is worth the investment.

I’ve built an Intel p4 541 w/ DDR2 1GB of ram 5-5-5-18 and it sucked! Then I built a Duo Core 2 e6600 with DDR2 2GB of ram 5-5-5-18 and it’s was better for 2007. But as technology advances and the person decide to upgrade you’ll see a great difference. I upgrade to Duo Core 2 e8600 w/ DDR3 9-9-9-24, enormous difference. NO need to overclock.

Moral of the story is, yeah you can overclock for a temporary solution, and however sometimes overclocking is not the greatest solution. Factory standards were set for a reason, if you want stability stay where you are or upgrade your entire system. Inexperienced users could fry up your entire computer by overclocking their ram. But if you still care to learn more about this get in contact with your motherboards manufacture, although some may not give you the answers you’ll like, but you’ll still find some boneheads that will in a SAFE manor.

OCZ also sells overclocked memory chips if you're still interested.