Ive got 4gb of ram in a G5, and while vista 64 buisness reports in system 4gb installed, taskmanager says that only 3055mb is actually used. Is this a known issue, are their workaround? Is it caused possibly by efi firmware or maybe even bootcamp?

Windows doesn't work good with 4096MB Ram (4GB). Having know problems, and this problem is one...

PS. Mac G5 (if is a real G5 = PowerPC processor) can't run BootCamp. If you need run Windows system try in old Microsoft VirtualPC.

Sorry, nothing to do.

Well I dont know exactly what kind of mac it is. It runs leopard, I know that, and I am using bootcamp to boot into vista. I have a 22-24 inch screen, its all in one. Says iMac on the back, and the stand has a circular cutout where the cord feeds through.

I have several vista machines with 4gb or more of ram, and they dont have any issues ( x64 versions, all of them ). This iMac is running 64 bit vista, and in theory should address 4gb+ of ram.

If run BootCamp doesn't be a G5. He's a Intel Processor.

First, you tell:

Originally Posted by MSFanBoy

Ive got 4gb of ram in a G5, and while vista 64 buisness reports in system 4gb installed, taskmanager says that only 3055mb is actually used. Is this a known issue, are their workaround? Is it caused possibly by efi firmware or maybe even bootcamp?

Before:

Originally Posted by MSFanBoy

Well I dont know exactly what kind of mac it is. It runs leopard, I know that, and I am using bootcamp to boot into vista. I have a 22-24 inch screen, its all in one. Says iMac on the back, and the stand has a circular cutout where the cord feeds through.

I have several vista machines with 4gb or more of ram, and they dont have any issues ( x64 versions, all of them ). This iMac is running 64 bit vista, and in theory should address 4gb+ of ram.

You haveing problems to run machines with 4GB RAM ?

If doesn't have, problem is solved?

Cheerz,

No? Problem not solved. I have 8 of these Intel iMac machines running vista, and they all have 4gb+ of ram, and they report 3055 ram.

Is this a known issue, and is their a solution?

I don't know this bug, but see:

Windows need allocate some memory for on-board videocard, like a ~388mb/ram.

Maybe have some temporary program or file "eating" your memory.

In case, try format and re-install Windows using latest BootCamp drivers included on 10.5.2 update.

You sure that it's the x64 version of Vista. It sounds to me like you're using x86. As you mentioned x64 should run 4GB+ with no problems, however, it may well behave very differently with bootcamp.

They are infact x64 machines, running x64 versions of vista.

As I've stated before I do believe this seems to be a hardware limitation of the iMac's themselves, wether in the mobo, the EFI or something else.

I am wondering though if this is a known issue, and might have a known work around, or a concrete answer as to what is causing the issue.

Is a know problem, maybe you need Microsoft Support, because, if you have a PowerPC processor on you Mac, is not good for run Windows.

Try look in Apple Menu -> About This Mac

It show as PowerPC or Intel Core processor?

The white Intel iMac only supports 3GiB RAM. This is a function of the Intel Centrino chipset used. The model ID is 6,1. The silver model - 7,1 - supports 4GiB RAM.