DRAM voltage

[Godzilla]

i have my DRAM voltage set to 1.64v in BIOS, but according to HW Monitor it fluctuates between 1.67 and 1.69v on load!

Is this normal?

 

[EarthDog]

More or less, yes. It seems to be over volting a bit.

 

[redduc900]

I wouldn't put too much faith in HWMonitor for reading the correct DRAM voltage from within Windows. Instead read the voltage from the 'Power' screen--> Voltage Monitor--> DRAM Bus Voltage in the BIOS.

 

[Godzilla]

what does the DRAM voltage have to be within 0.5v of? or is it 0.05v?

 

[redduc900]

The voltage differential between the DRAM Bus voltage and the QPI/VTT (or Uncore depending on the BIOS) voltage needs to be <= 0.5V. Default QPI/VTT voltage is 1.15 - 1.2V, w/ default DRAM voltage normally at between 1.64 - 1.66V. The absolute maximum DRAM voltage as spec'd by Intel for the i7 920 is 1.875V, which means no more than 1.35 - 1.375 QPI/VTT voltage. Although you'll see plenty of folks running considerably higher than 1.35V Uncore, like upwards of 1.5 or more for higher BCLKs and DRAM frequency of > 2000MHz.