9600M GT Ram

[glenncal]

I recently noticed that when using the 9600M GT on my UMBP, if I go to Activity Monitor, I get 1.75GB of RAM listed under the pie chart representation. When comparing to istat, it seems that 256 MB of RAM is being used as "wired". Is this how it is supposed to be?
I was under the impression that the 9600M GT is supposed to have 256MB of dedicated RAM in my model, which should allow the full 2GB to be used. There still is a substantial increase in graphics performance, if I choose between the "Better Battery Life" and "better Performance" options, but the Ram listed shows as 1.75GB nevertheless.
I should note that I am currently using Snow Leopard (which obviously might not be the final version), but I wanted to make sure that what I am seeing is not what is supposed to happen. I'm not sure whether I had the same issue in Leopard.

Thanks

 

[iLog.Genius]

You'll never have the full amount of RAM. The OS will always take up some. The memory you see being in use is the OS not the 9600M GT I believe. If you switch to the 9400M, more memory should be used up.

 

[glenncal]

I'm talking about the number directly below the pie chart in Activity Monitor though. Shouldn't that be the total RAM available to the system?

Sorry for the double post, but the thread had fallen to the 2nd page. Can anyone with a UMBP w/ a 9600M GT post what he sees in Activity Monitor under the pie chart (as the image attached shows)?

 

[Brandon Heat]

oh crap wait.. im not on the 9600.. one sec

 

[glenncal]

Thanks. It seems that it showing me 1.75gb is wrong then, I think. Sorry to bother you further but would it be possible to check what it shows when using the 9400M card instead.

Edit: So it shows you 4GB for the 9400M too. That's weird as I thought that would be the problem. Guess I'll have to go back to Leopard and see whether the problem persists.

 

[Brandon Heat]

i jus switched and checked.. its exactly the same 4GB

 

[glenncal]

Update: I tried various things to resolve this issue:
1) Clean install Snow Leopard from scratch. Result: still 1.75GB
2) Clean install Leopard. Result: 2GB as supposed.
3) Upgrade Leopard installation (in step 2) to Snow Leopard. Result: Back to 1.75GB

Thus it seems that the 1.75GB comes from Snow Leopard. I noticed that Activity Monitor lists 256MB more in "wired" than the istat widget. If I add all of the RAM listed on the right of the chart, they add to 2GB nevertheless, but it seems that 256MB is being wasted/used in wired memory and not listed under the pie chart.
I am unsure if the memory is being wasted but is sure seems wasteful to have 256MB used for apparently no reason, when this doesn't happen in Leopard. However I do find it hard to believe that this is a Snow Leopard bug as it would be quite serious if 256MB were really being wasted.
Obviously there is always the fact that no one is certain whether the SL build I'm using is the GM one..

I'm thinking of posting this issue in the Mac OS X Forum instead of here as now it seems that the issue has more to do with Mac OS X than with the MBP. Specifically I'd like to find if someone else is experiencing this.