Do motherboards automatically set memory voltage?

Question

Let's say I have a motherboard whose stock PC3200 DDR memory modules are fed a standard 2.6 V. I now replace them with performance sticks, which according to the manufacturer need to get the "recommended" 2.75 V in order to work at their advertised timings.

Will the motherboard automatically adjust the memory voltage to 2.75 V ? If not, will the motherboard maybe choose looser latencies, and will memory modules then function properly at 2.6 V with no frequency decrease (still at 400 MHz) ?

Answer 1

The correct answer is 'maybe'. Most modern motherboards (try saying that fast 5 times in a row!) will check the memory to read its capabilities and spec (including voltage) from a small block of ROM on the memory stick (this is known as Serial Presence Detect, or SPD), but, in general, I have found that many 'tweakable' motherboards that let you alter such things as RAM voltage tend to leave the value set 'as is' when you add or change RAM - presumably because the board assumes you may have tweaked the value already. In summary, best to check.