OCing e6600, RAM 667 -> 1200

[BloodyIron]

Hey [H],

I am currently overclocking my e6600 from 2.4ghz to 3.015ghz. I dont recall if I dropped the multiplyer, but I cant get it stably past that. However at this point I never crash.

Now, I am currently running on sone muskin DDR2 667mhz RAM (dont recall exact model/SN/PN). I am considering upgrading to a set of this ( http://www.memoryexpress.com/Products/PID-MX18885(ME).aspx ).

I was wondering what kind of an impact in my CPU OCing this new RAM would have.

Oh, also, I'm running on a 680i SLI A1 (eVGA).

 

[aethelwulf]

Well, that depends on what FSB you're running. If the memory is limiting you, maybe you could get a bit more out of it. Assuming you're using the stock multi, then you're fsb is 335 (which is about the limit of that memory without OCing it). I don't know about how that RAM overclocks, so it might be holding you back here. You could try loosening the memory timings and see if that allows you OC the FSB and memory a bit more.

 

[BloodyIron]

Well, that depends on what FSB you're running. If the memory is limiting you, maybe you could get a bit more out of it. Assuming you're using the stock multi, then you're fsb is 335 (which is about the limit of that memory without OCing it). I don't know about how that RAM overclocks, so it might be holding you back here. You could try loosening the memory timings and see if that allows you OC the FSB and memory a bit more.

Do you suppose the upgrade in RAM will provide a much larger headroom, or am i barking up the wrong tree?

 

[Mithent]

The multiplier on the E6600 is 9x: 266*9 = 2.4GHz. 333*9 = 3.0GHz, which is what you're running at, give or take a couple of megahertz.

This may well be due to your RAM; the slowest you can run the RAM on a system with 333MHz FSB is approximately 667MHz (double the FSB speed, when at 1:1 FSBRAM; don't forget it's Double Data Rate RAM). RAM rarely overclocks very well, so it's entirely possible that it won't go much higher than its stock speed, at least without loosening timings and increasing voltage, and will be unstable if you try.

So, you can halve the speed of the RAM to find the maximum FSB (without overclocking the RAM). Therefore 800MHz RAM will support an FSB of up to 400MHz, which is up to 400*9 = 3.6GHz. 1066MHz RAM supports an FSB of 533MHz, and 533*9 = 4.8GHz. 1200MHz RAM could theoretically allow an FSB of 600MHz and a CPU speed of 5.4GHz.

However, these are speeds you'll never meet; not only will your CPU not get up to 4.8GHz (let alone 5.4GHz), the motherboard won't do a 600MHz FSB. My recommendation is to get 800MHz RAM, as 3.6GHz is a pretty decent overclock for an E6600 and 800MHz RAM is cheap. With very good cooling you might be able to go a bit higher, which would need 1066MHz RAM, but it's not necessarily worth it; depends how high you're trying to go. 1200MHz RAM is overkill.

 

[kalrith]

To test the max RAM speed, lower the multiplier on your e6600 and change the memory:fsb ratio to 1:1. This will allow you to test the RAM speed independent of CPU and FSB limitations. Loosening the timings on the RAM might also allow you to overclock it higher. It would really suck to spend money on RAM that did nothing for your overclock.