Why is 1.65V memory bad for Sandy Bridge Processors?

[ensignlee]

I just now read that Sandy Bridge processors are supposed to work with 1.5V memory instead of 1.65V memory in the Sandy Bridge thread. The tolerances are supposed to be +-5%, which 1.65V memory definitely doesn't fall into.

What exactly could happen by running my memory at 1.65V instead of 1.5V?

 

[Leaps-from-Shadows]

DRAM voltage at 1.65v is the upper limit for Sandy Bridge CPUs. You can run RAM at that voltage, but no higher -- otherwise you risk frying the memory controller on the CPU. The previous Nehalem-based generation of Intel CPUs was the same way.

 

[davcon]

^+1
taken from http://www.bit-tech.net/hardware/cpus/2011/01/07/how-to-overclock-the-intel-core-i5-2500k/2

"Memory Voltage: As with LGA1366 and LGA1156 CPUs, keep this value to within 0.5V of the VCCIO voltage to prevent long term damage to the CPU. By default, this is 1.1V, which means the 1.65V used by previous Intel DDR3 memory is still acceptable. However, more recent memory will be rated at 1.5V (or even 1.35V if you choose a low-voltage kit). Increasing the VCCIO voltage obviously gives you more overhead on your memory voltage (remember, add +0.5V at most or risk damaging your CPU)."

 

[ensignlee]

So if I already have 1.65V RAM, it'd be a relative waste of money to go and get 1.5V RAM to replace it? Just wanna make sure, especially since the closest my mobo will let me set my RAM voltage to is 1.64

 

[ensignlee]

Best answer selected by ensignlee.