T61p - 4 or 6 GB memory

[hopgarden53]

Hi,

is it better install 2 x 2 GB (= 4 GB) than 2 GB + 4 GB (= 6 GB - unofficially over 4 GB MAX) on a

a) T61p 6457-5GG
b) T61p 6457-CTO(WRJ)
c) X60 1707-YF8
d) X61s 7666-3AG

?

[RealBlackStuff]

a) 2x4 GB
b) 2x4 GB
c) 2+1 or 2x2 GB (only 3GB usable)
d) 2x4 GB

[hopgarden53]

Well, thanks.

Actually I was asking if there is a performance penalty in using "odd size" memories? If I have only one 4 GB simm ...

[RealBlackStuff]

Up to 2x2GB, the RAM will run in Dual Channel mode, the rest, above 4GB, will run in Single Channel mode.
Dual is slightly faster than single, but not by much, and not everywhere.
On such old machines you won't notice any difference anyway, so put in what you like/have.
If hunting for more, look for PC2-6400, they run slightly cooler than PC2-5300, and are also often cheaper.
They'll still run 'only' at PC2-5300 speed.

[MikalE]

I have a T510 with 6GB, only because I needed a 4 GB stick for my T500 to bring it up to 8GB. I took a 2GB stick and installed that in the T510 along with the installed 4GB. Worked fine. Dual channel, single channel, I don't know and don't care as long as it plays music without buffering.

The T510 is only used for streaming music and light internet use.

[Screamer]

Actually I was asking if there is a performance penalty in using "odd size" memories? If I have only one 4 GB simm ...

There will be an extremely small performance penalty on some video games, but it is only a 1-2 FPS difference at most. This should not affect any other programs, unless they tax your RAM's bandwidth intensively. My guess is that the Northbridge treats half of the 4GB SO-DIMM as a part of the dual channel setup, while the other half of the 4GB SO-DIMM is prioritized differently which might have caused that very slight frame rate drop.

If you were wondering about odd-sized RAM configurations not running in dual channel, here is my screenshot of 1GB + 2GB setup in dual channel. I suggest keeping the 2GB + 4GB configuration, it is not worth to drop 2GB of RAM for the extra 1-2 FPS in certain applications.

[hopgarden53]

OK.

Thanks for everyone!