Overclocking quad core

[cRaZyMiLk]

Hey guys


one quick question, if i am running a QX6700 which has an unlocked multiplier(10), and standard 266 FSB (=2.66Ghz) then is there any point buying say PC 8000 = DDR2 1000 MHz = 500 MHz

As i can just up the multi to say 13 which wouldl give me 3.4Ghz (266FSB x 13)

My other question is, if i did have the PC 8000 = DDR2 1000 MHz = 500 MHz memory and only running the FSB at the standard 266 would it still be better to have the 1:1 ratio? and if not what would be a better ratio and why?

Thanks for your help


and hi btw

 

[Accord99]

In general, there's no benefit to running 1:1 ratio on a C2D platform. Best performance comes from running memory as highly clocked as possible (though it's not too big of a difference). For example here:

http://www.xbitlabs.com/articles/memory/display/core2duo-memory-guide_6.html

If you're aiming for 3.466GHz and end up purchasing the DDR2-1000 memory, I would suggest using 9x385, using a 4:5 memory ratio to achieve a memory speed of 962MHz. Depending on the chipset you used, you may end up wanting to use a higher FSB, I only suggested 385 because on many P965 based motherboards, going over 400MHz will cause a memory performance decrease. This may not be the case if you have a 975x or a Nvidia based motherboard.

 

[cRaZyMiLk]

Originally posted by: Accord99
I would suggest using 9x385, using a 4:5 memory ratio to achieve a memory speed of 962MHz.

Thanks m8
Could you explain to me how that sum is worked out so i can undertsand it better.

 

[Accord99]

The 4:5 mean ratio means that the your base memory bus will run 1.25X faster than the base FSB clock. With a 385MHz FSB, the base memory bus is 481MHz, then multiply by two because of the double data rate to give you 962MHz.

 

[cRaZyMiLk]

Wow Thanks Accord, its beginning to make some sense now. I have beening trying to figure out mem ratios for ages and how you worded that is very simple to understand( i think)

So in theory
If i have decent water cooling with DDR2-1000 memory and the right chipset i could have a FSB of 400 on a 4:5 ratio meaning the mem will be runnning at the rated 1000 and i would have an overclock at 3.6 (400x9)?

Is that right?

Also ona side note what other ratio options to you general get?

 

[JAG87]

Thats correct.

Just remember that your ram cannot, ever, run slower than your FSB. That means that if your FSB is set to 400, your ram will be running at DDR2-800.

Then by using dividers, you can get your ram speed higher. you can use 4:5, 2:3 and so on.


*edit*
if you plan on doing 400 fsb you better arm yourself with a good 965 board. no other chipset can handle that fsb with kentsfield.

 

[theprodigalrebel]

I will just add in that you don't have to necessarily purchase memory marked for DDR2 1000/1066 at $300-400 prices. If you look around and ask questions, you will find lots of DDR2 800 kits in the $200-$250 range that consistently hit over DDR2 1000. Look around these forums and people's signatures for their configs.

 

[cRaZyMiLk]

Originally posted by: JAG87
Thats correct.

*edit*
if you plan on doing 400 fsb you better arm yourself with a good 965 board. no other chipset can handle that fsb with kentsfield.

Thanks guys
Anyone suggest a good 965 board that should hit 400fsb with a kentsfield??