Can someone explain voltage settings to me?

sturmtruppe · 22 Aug 2010 at 18:55

Hi all,
having a conundrum trying to get my ddr2 ram to run at 800mhz on my board. Both the ram and MB natively support (supposed to) 800mhz, however it needs to be set manually in the bios.

When I do this however, and open up cpu-z my cpu voltage is around 1.2-1.3 - whereas usually it is around 1.1-1.2.

I'm not exactly sure why it affects cpu voltages when simply changing the ram speed, can any one explain whether i have to set cpu voltages manually and what it should be set to?

Thanks

Edit;
I should add that i set it manually to 1.125 and all works ok, but im worried it may be too low.

egnshane · 22 Aug 2010 at 19:33

Just run prime95, if the voltage is too low then it will not pass.

RJC · 22 Aug 2010 at 19:57

What Corsair ram are you running, as most require 1.8v to 2.2v depending on modules.

sturmtruppe · 22 Aug 2010 at 20:16

http://www.corsair.com/_datasheets/TWIN2X4096-6400C4DHX.pdf

It does state 2.1v to run at 4-4-4-12 800mhz, however i want to make sure the cpu voltage is correct before making any changes to ram.

@egnshane I've set vcore at 1.100v (lowest available setting on my MB) How do i use prime 95? I've just run it and hit ok to run the 'blend' test. Ran for 5 mins completed 2 tests with 0 errors for each core. Would that be sufficient enought to keep at the voltage im running?

egnshane · 22 Aug 2010 at 20:23

No you want to run it for 2 - 3 hours to have an indication its stable, its best to have the voltages as low as possible. It keeps heat down.

Alfizzle · 25 Aug 2010 at 21:30

if your not overclocking leave cpu voltage on auto,
setup your ram: voltage 2.1v, timing: 4-4-4-12 speed:800mhz

im not sure but the power circuitry on your board might not be that good, it might be leaking voltage to the cpu because the ram voltage is quite high + your running 4 sticks.

i personaly say you have nothing to worry about, aslong as it is stable and your temps are within spec.