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pubwvj

macrumors 68000
Original poster
Oct 1, 2004
1,902
208
Mountains of Vermont
I'm going to get a new PowerBook 15".

I plan to order it with 1GB in one slot so that later I may add another 1GB in the second slot.

The question is how much power does each 1GB stick of RAM consume? Is it significant enough to raise the heat load and increase power usage such that one would get noticeably less battery life? A portion of the question might even be if one had more RAM would the increase in system efficiency (less hard disk access for paging) result in improved power usage.

I ask because with my PowerBook Pismo there is a noticeable difference in power consumption between having one 512MB RAM card vs two 512MB RAM cards installed.
 

shadowmoses

macrumors 68000
Mar 6, 2005
1,821
0
More RAM shouldnt effect your battery life, if anythng it may increase it as it will stop the HD from spinning up so much,

SHadow
 

crazzyeddie

macrumors 68030
Dec 7, 2002
2,792
1
Florida, USA
shadowmoses said:
More RAM shouldnt effect your battery life, if anythng it may increase it as it will stop the HD from spinning up so much,

SHadow

Exactly, and RAM has been getting more and more efficient. This is really a null issue, as more RAM theoretically takes more power, but the more RAM, the less time the hdd spends swapping data.
 

Lucky8

macrumors regular
May 18, 2005
218
0
I didn't notice any different before and after I added the 1GB RAM.
 

gekko513

macrumors 603
Oct 16, 2003
6,301
1
This complicated article says that 512MB of DDR2-533 RAM draws ~2.7W of power during a moderate workload. That's more than the hard drive uses when reading or writing. Just ~0.5W during low usage, though.
 

Demon Hunter

macrumors 68020
Mar 30, 2004
2,284
39
gekko513 said:
This complicated article says that 512MB of DDR2-533 RAM draws ~2.7W of power during a moderate workload. That's more than the hard drive uses when reading or writing. Just ~0.5W during low usage, though.

I thought DDR2 was quoted at 1.8v? Is that just the average? Because DDR needs 2.5v...
 

Flyinace2000

macrumors 6502a
Sep 28, 2004
666
0
1.5 gb of ram here and i can squeeze (like no airport, BT, screen on the lowest setting, CPU on reduceD)
 
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