Oui.
If you want to address more than 3 gbs of RAM you need a 64 bit OS. If you have the latest and greatest Intel processor, as opposed to the crud that is packaged in a Mac, I would recommend that you plunk down a bit more and install Vista 64 as a dual boot config.
There you can explore whether there is a real world benefit, as opposed to an imagined one, running an OS that can address more than 3gbs of RAM. Real world testing of CS4 on Vista 64 does not show a clear benefit in having that greater than 3gbs of RAM in terms of speed or anything else, but that’s just the facts getting in the way of many people’s ill-considered but dearly held opinions.
Unfortunately although Win7 (actually Vista SP3) is likely to be unleashed this year, which seems to smooth out some but not that many of the many glitches in Vista, Win 7 continues the Microsoft tradition of arbitrary changes to driver models. This will be especially bad for the 64 bit version as Vista 64 bit drivers are lacking for many common, recent peripherals and that OS has been available for a long time and is being foisted on unsuspecting buyers of low-end laptops and boxes.
Under a 32 bit OS, the most the application can see is 2 Gig. With the /3GB switch, an application can see 3 Gig.
With a 64 bit OS, the application can see up to 4 Gig.
But the application cannot use all of that address space – some of it gets taken up by the OS, some by the application binary, etc.
So, yes, you are seeing as much as your OS will let you. Moving to Vista 64 would help (and let you run the 64 bit application to use the full 6 Gig).
I have an Intel Core 2 Quad Q6600 2,4 GHz with 8 Gig Vista 64bit CS3 shows me available Ram of 3255 MB
Should it not be possible to see 4 Gig, "use" 4 Gig for CS3 and run the other applications with the rest?
Thanks for some input
CS3 is a 32 bit application. Move up to CS4 and you’ll see plenty of RAM.
Bob
Matthias – again, Photoshop CS3 is seeing 4 Gig on your system, and Photoshop is telling you how much of that 4 Gig is really available for use.
Thanks for the help. I am not sure I understand. Of the 6GB in the system, CS3 only shows 1.6GB available meaning the remainder of ram is not available because it is used elsewhere or is CS3 just not able to recognize more than 1.6GB? Nothing else is running except the OS, VISTA 32. System specs from control panel confirm 6GB are installed.
I would move to CS4, however the move is not in the cards just yet.
Bruce: You would have to move to Vista 64bit for PS to see all the RAM available on your system. It is the OS that dictates this and the fact that CS3 is a 32bit app. You would need to update both. If you update to CS4, you would only use the 32bit version of PS because the OS is still 32 bit.
I suspect he went 6 gigs because the I7 loves 6 gigs and runs faster as tests have shown. However, not on a 32 bit operating system.
But would an x86 OS even recognize 6 gigs? Maybe he has x64 without realizing it.
I think Vista will report all of the installed RAM but won’t be able to use it.
Bob
Why in the world would you put six gigs of RAM into a machine with a 32 bit operating system?
Bob