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Corsair Dominator GT 2000Mhz not running at rated speeds.

Last response: in Memory
October 13, 2010 8:44:19 PM

Hi, I just got my Dominators today 6Gb of them. I installed them and tried the XMP function but the failed overclocked message comes out. So I then try to do the manual overclock, now CPU at 3.3Ghz and RAM at 1600Mhz 7-8-7-20 1T, Vcore 1.275, VRAM 1.74 and QPI/DRAM V 1.300. I would like to know how to run it at higher frequencies and clock my CPU to around 3.6Ghz. I am not sure about the voltages and all. I am using an i7-920 DO, P6T Deluxe V2. I've tried raising the BCLK to 183 and that makes the DRAM frequency rise to around 1833 but it would not boot or I would get a BSOD at the windows screen. Do I need to change the voltages or something and what would be safe?
a b } Memory
October 14, 2010 8:44:22 AM

You need to read a guide on CPU OCing to OC your CPU. Here is a bit of an explaination that I posted in a different thread to give you an idea:

"There is a "Base Clock" which has a default value of 133MHz for all i3/5/7. Both the CPU and RAM speed come off this with a "Multiplier". For example your i7 930 has a 22x multiplier (I think) and thus:
22 X 133MHz = 2926MHz = 2.9GHz
This is the clockspeed of the CPU.

The RAM also has a multiplier, its default value is 10x:
10 X 133MHz = 1333MHz
This is the RAM speed.

Though the RAMs multi can be changed. It has values of 10, 8 and sometimes 6. Notice that you cannot get 1600MHz RAM speed from any of these multis? Instead to get a RAM speed of 1600MHz the Base Clock must be raised to 160MHz. This would create:
10 x 160MHz = 1600MHz

But remember that the CPU speed also increases from the Base Clock with a Multi of 22x. This means the the new CPU speed would be:
22 x 160MHz = 3520MHz = 3.5GHz

This is an OC which you are not ready for with your stock cooling. Thus the CPU Multi must be lowered. Using a multi of 18x will allow the CPU to run at stock speeds:
18 x 160MHz = 2880MHz = 2.9GHz"

You say that you have your DRAM voltage at 1.3V, I do not believe you. You should find your actual voltage and set it to the spec of the RAM, though don't set it above 1.65v.

Hope that answers most of your questions.

Also I would not recommend setting the RAM to 2000MHz, you won't see any performance. If your OCing and you get up to 200MHz bclock go for it though don't go out of your way. To reach a 200MHz bclock will require some overvolting of the VTT. I'll link you to a guide of this:

What you need to know is under step 1 but read the stuff before this also.
October 14, 2010 11:48:14 AM

Thanks for the info, I have already reached my target. It turns out that the QPI/DRAM voltage just needed to be bumped up a bit more from the 1.3V and I did not need to set the VDRAM that high so I turned it down to 1.7V. Gonna tweak the timings and see if I can lower the voltages for the DRAM.
a b } Memory
October 14, 2010 12:22:45 PM

You are not supposed to run RAM above 1.65v. What voltage is the RAM rated for? At those low speeds it should run fine even undervolted.