Power Usage of RAM

[Stiganator]

How much power does DDR RAM use in watts? I have seen non-specific references to RAM using 10 watts per 128 MB but that doesn't seem feasible since that would mean 1GB system would consume 80watts!!! That means servers would be using 8GB or 640 watts just for RAM. Any help here? My logic is that it is 2.8V x ~10mA per bank, which is 0.028 watts per bank, can anyone confirm some numbers either way?

 

[Megamixman]

Depends completely on the IC used. Both Samsung's 128Mb IC's and 1GB IC's are rated for 1.5W Nominal power usage. So if that 8GB is made of 8 sticks each with 8 1Gb IC's on them you have 64 IC's. Multiply that by 1.5W each to get a grand total of 96W. most people have 1 or 2 512MB sticks with 8 each so they have 8 or 16 IC's using 12 or 24 W, depending on the number of sticks they have.

 

[Mark R]

It's about 10 W per GB of DDR 400 (peak load), and considerably less when idle.

A typical 512 Mb chip will use about 250 mA (2.6V) under worst case conditions. You need 16 of these for 1GB - so 0.25 x 2.6 x 16 = 10.4 W
1 Gb chips use about double the current per chip.

 

[Megamixman]

That is interesting. How come Samsung can rate their 128Mb Chips for the same Nominal Power usage then?

 

[Stiganator]

Thanks guys very helpful