I'm confused, please help - overclocking/memory

Ok so I'm trying to overclock my e6600 with corsair ddr2-800. I know the basic steps to overclock where you raise the fsb in order to gain ghz's, when there is not enough vcore you raise it also and blah blah blah....

most confusing part for me is that the ratio factor, how you guys calculate it and why when raising fsb the memory goes with it? I heard you can unlink it, but i really dont know where would i find it in bios. The mobo is p5q se2, i found the option for dram ratio but it gives me weird numbers starting from like: 667,837,1333 so on... i really dont get this part.

I think that in my case i need to lock my ram because when i oveclocked it to 3.2(350*9) the cpuz showed my that my rams works on 450mhz. Where they should work on 400(400*2=800), i ran some tests with negative results and i dont think it is vcore cause i raised it to 1.35~1.4, so it should be fine.

some guys said this for my cpu:

"Personally, I set my RAM speed and lock it right up front to reasonable level I expect to get to, don't leave it at AUTO and have it raise with the FSB....there's no point.

For a Core 2 Duo system, and with your RAM, I would set it to run at 650Mhz at stock timings and voltage. When you hit 350 FSB you can slowly raise it with the FSB to stay at 1:1 until the RAM maxes out......"

I' really getting confused right now even now when i'm writting it ...... question is.... in order to have ratio 1:1 for instance and stable system, where i know i cant obtain fsb 1600/4=400 = ddr2(800/2). so if i want to get 1:1 ratio what should i do.. .. i dont know. :/

thanks in advance

The 667/800/1066 setting is the final ram speed assuming the FSB is at default for your chip.

When you raise the FSB the ram speed goes up to, and the ram numbers are not re-calibrated.



What you need to do is set the ram to the slowest setting possible, go about your overclocking business, and then see how much you can turn the ram back up afterwards.

Bobnova said:

The 667/800/1066 setting is the final ram speed assuming the FSB is at default for your chip.

When you raise the FSB the ram speed goes up to, and the ram numbers are not re-calibrated.



What you need to do is set the ram to the slowest setting possible, go about your overclocking business, and then see how much you can turn the ram back up afterwards.

Click to expand...

I found it:

FSB : DRAM
1:1 = 333 MHz : 667 MHz
4:5 = 333 MHz : 833 MHz
2:3 = 333 MHz : 1,000 MHz
5:8 = 333 MHz : 1,066 MHz
3:5 = 333 MHz : 1,111 MHz
1:2 = 333 MHz : 1,333 MHz

I think that what my mobo gives me as options- 667,833,1000 so on.
So it means that by having fsb 333 my ram should be 667, but when i checked it at cpuz it was somewhre at 445 something, and what you mean by that the rams are not re-calibrated

thanks

and

how could i lower my ram on p5q se2 if i cant find it anywhere on the web, or its better to unlink the fsb/ram so they work separately

?

so i really dont know how could i get my e6660 with 2gbs of ddr2-800 to work on let say 3.4 and ratio 1:1.

Help

Hey & Welcome to OCForums

The DRAM Ratio of DDR2-533 will give you a 1:1 ratio with the FSB. DDR2-533/2 give you a base frequency of 266 MHz, which is the same base frequency of your E6600. It is 1066 FSB/4 to get the 266 MHz base.

The guys talking about unlinking their RAM from the FSB have nForce chipsets. The Intel P45 chipset doesn't have that option.

If I remember correctly, my E6600 needed 1.5v to run at 3.6GHz (400x9). It was water cooled, so temps where not an issue with the vcore set that high.

JLK03F150 said:

Hey & Welcome to OCForums

The DRAM Ratio of DDR2-533 will give you a 1:1 ratio with the FSB. DDR2-533/2 give you a base frequency of 266 MHz, which is the same base frequency of your E6600. It is 1066 FSB/4 to get the 266 MHz base.

The guys talking about unlinking their RAM from the FSB have nForce chipsets. The Intel P45 chipset doesn't have that option.

If I remember correctly, my E6600 needed 1.5v to run at 3.6GHz (400x9). It was water cooled, so temps where not an issue with the vcore set that high.

Click to expand...

First thanks for reply...

how can i put ddr2 to 533??? first question... you mean i would have to lower my ram so it will work equally but would that decrease the performance? (this means if i want 1:1 without overcloking right?) Another question is that do you think that with TRUE heatsink i could obtain 3.6 or should i aim for less. Im concidering working on this cpu for sometime.

Thanks

?

oh yea and is it true that rule of thumb for overclocking vcore should be that .05v every 100 mhz?

Is DDR2-533 not a DRAM Ratio option?

You would see a small decrease in performance by lowering the RAM Ratio to DDR533 without overclocking, but you probably wouldn't notice without running specific RAM benchmark tests. If you can reach your goal of 3.6GHz the RAM will be at DDR800/400MHz, which is right where you want it.

Don't go straight for 3.6GHz. Try 3.0GHz (3000/9=333FSB) 1:1, then 3.1GHz (3100/9=345FSB). Run a stress test like Prime95 torture test small FFT for a few minutes as you increase the CPU speed. The RAM will be underclocked, and you won't need to worry about it being unstable.

Monitoring the CPU core temps as you overclock & run Prime95 will let you know if the TRUE can keep your CPU cool enough. You wanna keep it under 65C.

Edit: That vcore rule didn't apply to my E6600 until it got over 3.3 GHz with 1.35vcore, which is default. 3.4GHz needed 1.40v, 3.5GHz needed 1.45v, 3.6GHz needed 1.50v. Your CPU may need a little more or a little less - that's why you should step up and test with Prime95.

JLK03F150 said:

Is DDR2-533 not a DRAM Ratio option?

You would see a small decrease in performance by lowering the RAM Ratio to DDR533 without overclocking, but you probably wouldn't notice without running specific RAM benchmark tests. If you can reach your goal of 3.6GHz the RAM will be at DDR800/400MHz, which is right where you want it.

Don't go straight for 3.6GHz. Try 3.0GHz (3000/9=333FSB) 1:1, then 3.1GHz (3100/9=345FSB). Run a stress test like Prime95 torture test small FFT for a few minutes as you increase the CPU speed. The RAM will be underclocked, and you won't need to worry about it being unstable.

Monitoring the CPU core temps as you overclock & run Prime95 will let you know if the TRUE can keep your CPU cool enough. You wanna keep it under 65C.

Edit: That vcore rule didn't apply to my E6600 until it got over 3.3 GHz with 1.35vcore, which is default. 3.4GHz needed 1.40v, 3.5GHz needed 1.45v, 3.6GHz needed 1.50v. Your CPU may need a little more or a little less - that's why you should step up and test with Prime95.

Click to expand...

so if im not wrong to have 1:1 on 3.0 ghz my ram should be 666 (333fsb*2)... is it right?

and now the technical question... how do i lower ram on p5q se2???

You're absolutely correct. Running 3.0GHz (9x333) with the RAM 1:1 it will be at DDR667/333MHz.

According to page 2-13 of the manual, goto the AI Tweaker and change the DRAM Frequency from AUTO to DDR2-533. You might also need to change the FSB Strap to North Bridge from AUTO to 266MHz.

It is also very important that you change the PCIe Frequency from AUTO to 100MHz.

JLK03F150 said:

You're absolutely correct. Running 3.0GHz (9x333) with the RAM 1:1 it will be at DDR667/333MHz.

You might also need to change the FSB Strap to North Bridge from AUTO to 266MHz.

It is also very important that you change the PCIe Frequency from AUTO to 100MHz.

Click to expand...

what strap to north bridge and pcie freq will do for me?? - stable?

And you dont even know how thankful i am for your help.

ps. when you'll be by chicago anytime let me know so i'll show you around some best polish clubs

Thanks- i will keep you updated on my progress.-thx

The FSB Strap to NB basically only changes the available DRAM ratios.

The PCIe Frequency also controls the PCI frequency. Overclocking those can cause all sorts of problems, such as video crashes, sound, network and data corruption.

Lots of in Chicago? Sounds Fun! lol

JLK03F150 said:

The FSB Strap to NB basically only changes the available DRAM ratios.

Lots of in Chicago? Sounds Fun! lol

Click to expand...

So if you told me to change it to 266 you mean to even it out with stock fsb, but if i want overclock it should be changed to whatever fsb im looking for??

No, you want to leave the strap at 266MHz because it matches your CPU's FSB. If you had an E8400 (9x333) then you would want to use the 333 strap.

JLK03F150 said:

No, you want to leave the strap at 266MHz because it matches your CPU's FSB. If you had an E8400 (9x333) then you would want to use the 333 strap.

Click to expand...

oh ok so you just match it with the manufacture stock speed and this is it. Got it

I guess after work ive got plenty things to do...

Thanks again-owe u

problem

JLK03F150 said:

The FSB Strap to NB basically only changes the available DRAM ratios.

The PCIe Frequency also controls the PCI frequency. Overclocking those can cause all sorts of problems, such as video crashes, sound, network and data corruption.

Lots of in Chicago? Sounds Fun! lol

Click to expand...

When i try set fsb strap and pcie freq I can not set the dram ratio to be 1:1 with the fsb. Why?-it gives me 776 something 1st available.

The PCIe freq and the ram are not going to be linked in anyway.

I would really suggest reading this.

http://www.ocforums.com/showthread.php?t=515316

you should find the limits of each part of your computer. If I was you and you have 800 mhz ram over clock it. you should be able to do 1000mhz with 5-5-5-15 timings.

e6600 oc update

So heres my stable (i think ) oc update so far.... I'm actually running 372*9 tests now with 1.362 vcore in bios/ 1.312 cpuz-->let you know later

three questions:

1) why after prime95 the vcore went to 1.240 from 1.39(is this normal)?
2)for how long i should run prime95(small fft) to be pretty sure about stability?
3)any comments you guys could give me?-in advance thx

?