Getting a new 1333mhz Quad Core what speed memory should I get?

[flyhiloone]

Hey,
Just have a simple question, I am planing on getting a q9300 and overclocking it. My question is what DDR2 ram speed will work the best for overclocking. I am planing on buying Corsair brand so i could get the plain jane 800mhz ram or the 1066 dominator. Which should i get and why?

Thanks in advance..

 

[dechy]

Depends on what your overclocking goals are. Using PC-6400, you can safely go to 3.0GHz (7.5*400) and never even tweak your RAM.

There's been success getting the q9300 to 3.5GHz, but that pushes the RAM to 460MHz+, which is quite high for PC-6400.

If you want to make sure your RAM won't be the issue, get PC-8500, gives you massive headroom, more than you'll ever need to OC that CPU.

 

[Guest]

It does depend on what you want your FSB to be.

I'm not sure if the 9300 has a multiplier of 9 like the Q6600 does. If that is the case, you may be able to get stable at 3.6Ghz without touching your memory.


Also, some DDR2-800 memory is known to be a good OCer and can be stable at speeds of 533Mhz which is 1066 memory.

 

[aevm]

The Q9300 has a multiplier of 7.5. BTW, not being an integer causes problems with some mobos, from what I hear.

@OP: consider a Q9450 or Q6600 instead.

 

[flyhiloone]

Hey thanks for the replies guys.

First of all I would love to buy a q9450 unfortunately I like to buy from newegg and they haven't had one on their site for 3 weeks. In fact i can't even find it listed now.

Can somone explain why its not neccesary to pair similar ram speeds to motherboard speeds. i.e. q9300 has a 1333 fsb why is it not important to get ram that is 1333mhz (ddr3) Or maybe it really is. Explain if you can...

Thanks

 

[aevm]

www.ncixus.com has the Q9450. OK, it's special order, 2 weeks waiting, but it's there. Kind of weird, the version with a HSF costs $24 LESS than the version without it. They are actually paying you to get the HSF off their hands???

 

[dechy]

To simplify things, CPUs are quad pumped, so whatever FSB a CPU is rated at, divide by four. For example, the q9300 has a 333MHz quad pumped FSB.

RAM is self explanatory through the DDR acronym; double data rate. So, DDR2-800 = 2x 400MHz

In all technicality, you could run at low as PC-5300 (DDR2-667) for the q9300 and it would work fine, since they'll both run @ their rated 333MHz.

Whe OC is involved, you need to think how high you wanna go. Easiest way is to step up the RAM to the next level, so in this case PC-6400 (DDR2-800). This would mean you could OC the CPU FSB to 400MHz and get 7.5 x 400MHz = 3GHz like I stated in my first post. Chances of you CPU not being able to hit that is extremely slim, and the RAM obviously will since it's rated at 400MHz.

If you wanna go higher, that's when you need to factor in trying to OC the RAM as well, or just go to the next level of RAM (PC-8500, DDR2-1066).

DDR3-1333 is actually 667MHz, and you most definitely don't need that.

 

[flyhiloone]

Dechy,

Thanks alot for your reply. That helps out alot. I think i am going to go ahead and get the dominator ram as i am planing on trying to get the maximum oc out of my system.

Thanks everyone

 

[mindfields]

Even i have one query.

I'm planning to buy a Q9450 along with DDR2-1066 modules, since the memory is not synchronous with the FSB, how does it affect performance when you are NOT overclocking? i meant which would be better? Running the CPU with DDR2-667 in synchronous mode or running it with either DDR2 800/1066?

 

[MrMr]

Also, some DDR2-800 memory is known to be a good OCer and can be stable at speeds of 533Mhz which is 1066 memory.

Well I dont think that would be smart. How long do you think 800mhz memory is going to last at 1066mhz?

Been running mine for a year+ @ 1050. No issues. As long as they use D9 chips (like your Patriot ram) with the voltage @ 2.1, then all is good. If you set your timings to 5-5-5-12\15, you can easily reach 1066 stable.

 

[Guest]

Also, some DDR2-800 memory is known to be a good OCer and can be stable at speeds of 533Mhz which is 1066 memory.

Well I dont think that would be smart. How long do you think 800mhz memory is going to last at 1066mhz?

With value ram it wouldnt be smart.

With high quality ram and if done properly it is fine and will last a long time.

High quality DDR2-800 is still cheaper than DDR2-1066. Thanks for stopping by.

 

[dechy]

True, but companies don't outright guarantee that modules will overclock to much higher ratings even from the best (Dominator series, Viper series, Reaper series). There's still a chance the things won't overclock much past their standard rating, even overvolted & relaxed timings (albeit a slim chance, but it's still there)

The extra 20$ difference between (for example) Viper 800 or Viper 1066 is a small price to pay to make 100% sure there's no OC'ing problems with your RAM and you can focus on something else if your OC isn't working.