Newb's question about OCing RAM

[Ronarch]

Hi guys,

I am using Corsair Vengeance CML8GX3M2A1600C9W DDR3 1600 8G Kit.
So as my understanding, this pair of RAM can go to 1600Mhz by OC.

In the UEFI BIOS, I switch the DRAM Frequency from Auto to 1600 Mhz.
The result is that, in the Memory page in CPU-Z
It changed from

to

So, it's still just 800Mhz, why?
Is it because of dual channel? I actually have got 800Mhz x2 = 1600Mhz?

Thanks for helping

 

[catnipkiller]

800x2 = 1600
ddr=double data rate
so this is the right speed.

 

[Ronarch]

One more question,

I am using i5 2500k and the CPU bus speed is 100Mhz
So for the FSBRAM ratio shown in above pictures,
shouldn't it be 1:8 when the DRAM Frequency is 800Mhz and 1:6.66 while that is 666Mhz?

It seems like the bus speed is 133Mhz, why?

Thanks for teaching.

 

[cadaveca]

ram bus doesn't run same speed as CPU bus, thanks to seperation by the System Agent domain. you are correct in it being based off of 133 MHz.


I run mine @ 1866 MHz, 9-10-9-27-41-6-14-8-155-8-29-1T, 1.5v. Which version are yours..2.12, or 8.16?

Just got the sticks yesterday, ran tests overnight, gamed today, and am good to go now. After the overnight testing, now running default IMC voltage, too.


Glad I bought 'em, really.

View attachment 44353

 

[Ronarch]

I run mine @ 1866 MHz, 9-10-9-27-41-6-14-8-155-8-29-1T, 1.5v. Which version are yours..2.12, or 8.16?

for the first 4 no., I think mine are 9-9-9-24...which can be seen in the pic.
But what are the following numbers? What are they? Where can I find mine?

 

[cadaveca]

they are "subtmings", available in BIOS to set, under the primary 4 in "Memory Configuration".

 

[Ronarch]

they are "subtmings", available in BIOS to set, under the primary 4 in "Memory Configuration".

Are they only about compatibility?

 

[cadaveca]

No. They adjust varying timings for the DIMM, like time taken between writes and reads, the time taken between refreshing the data on the ram, etc...they are critical to function, period, and not just for compatibility. they can affect performance, too.

Without adjusting them, reaching 1866 seemed impossible, and did not boot.