Solved 4GB virtual memory?

[markg2]

I'm thoroughly confused at this point having just ordered 2 ea 2GB memory sticks to replace the 2x1 sticks currently in the Thinkpad T61.

In determining if the OS + machine can address this amount of memory (I hadn't thought this was a problem when I ordered the memory this morning but now I'm not sure) I don't understand if it's a no brainer that 4GB is addressable or whether something called machine enabled DEP is necessary to address this memory?

Mark

 

[fseal]

Windows 32 bit can address 4 gig of ram with no other settings. (DEP is something else entirely).

However, some amount of that will be eaten up by hardware requirements. Sometimes a LOT like 0.8 meg or so. So expect to have only about 3.2 to 3.5 meg available totoal if you are using Win 7 32 bit.

If using 64 bit and the computer is not too old then it should all be available minus a few k...

 

[seavixen32]

Are you using the 32-bit version of Windows 7 or the 64-bit version?

If it is the latter all the memory will be used. If the former only 3.25GB will be recognised, but you still need the new RAM to use it.

 

[markg2]

Whew-

So if the OS (32 bit) overhead on 4GB could be as high as .8 how do I determine (curiosity) what my current overhead on 2GB is?

 

[fseal]

The hardware always uses memory from the 4gig address on downward. So with only 2 gig in the machine you can't really tell.

However, the biggest consumer of that space is the video card memory. You might be able to predict that if you have a 512 meg video card that your resulting usable ram would be about 3.4 gig. If it's a 750 gig then 3.1 gig or a 1 gig video card might leave you with only 2.8 gig!

I say "may" because even that is not set in stone (Depends on hardware/drive for the video), but it's "most likely".

 

[markg2]

Although the newly installed 4GB resolves to ~3.2GB the increased performance resulting from 2GB-->4GB is huge.

Mark