Max ram in 32 bit OS and graphics cards question.

[OS43]

So I have heard that GPU memory uses up some of the allowed system memory under a 32 bit OS, is this true?

If I have 4 gig or ram, and 1gig of ram on my GPUs, will windows see the 3.5gig max, or will it only see 2.5 because of the video cards?

If this is the case it is fairly lame, as my wireless adapter manufacturer (linksys) refuses to make 64 bit drivers.

 

[Maziar]

Recognizing RAM isn't related to the amoung of GPU u have
32 bit OS recognizes max 3.5GB RAM of 4GB

Also dont worry about the 3.5GB RAM, i had XP 64 with 4GB RAM and i had to install the 32bit version due to some games/printer problems and i did'nt see a single performance loss from 4GB to 3.5GB

 

[OS43]

Alright, heard the opposite a few times even though it doesn't really make sense.

 

[dengamle]

32bit xp and vista can address not 3.5 but 4GB. And because of things like ram on the graphics card is included in this equation, the amount of available system ram will be less than 4G

 

[arson94]

32bit OS's use 32bit memory addresses = 2^32 = 4294967296 bytes = 4GB. This is the most a 32bit OS can address, Windows and Unix alike. The problem is that MMIO (Memory Mapped I/O), video memory (onboard or on a discrete card), and even your agp apreture size are mapped within this 4GB of memory address spacing. Subtract all the addresses that your BIOS maps into memory from 4GB and you have the total amount of available address space for actual RAM. Of course, the PAE (Physical Address Extention) solution exists, but that's a whole other nest of **** to get into. I think you can actually compile kernels in Linux to support more RAM, but I think it's the equivalent of PAE in Windows. Also, MMIO is pretty much every periphreal in your computer. So, if you can manage 3.5GB or more under any 32bit Windows then I'd be happier than a pig in ****. If you can get 3GB or more then I'd be satisfied. Otherwise, I'd look into disabling some onboard crap that you don't need, decreasing apreture sizes, uninstalling extra devices that you don't use, or going 64bit in the OS department. Oh, I also found a good source that might be good reading for somebody. Hope ya'll find it useful....

http://www.hardforum.com/showthread.php?t=1035670

Arson94

 

[notherdude]

32bit xp and vista can address not 3.5 but 4GB. And because of things like ram on the graphics card is included in this equation, the amount of available system ram will be less than 4G

Dengamle speaketh the truth.

32 bit MS commercial OS can only address 4 gig of RAM. This limit is based on the scheme used in virtual addressing. A 32 bit binary number maxes out at 2 to the 32 power which is 4 gig. It's a limitation of the software, of the OS. Since the OS can only address 4 gig TOTAL if it will need to address any other memory in addition to your system RAM - in addition to your dimm sticks - it must reserve those addresses off the top of the 4 gig limit. The more video memory (in addition to a few other things) you have the more addresses must be reserved out of your 4 gig. Hence people usually end up with anywhere from 2.5 up to about 3.5 gig of usable RAM.

The fix for Vista or XP is to get a 64 bit version of the os.

This does not mean your system RAM is being used for the graphics card or for anything else, it lies there UNUSED, because of the inability of the OS to talk to it.

There are workarounds used in some other 32 bit OS and there was at one time a workaround in XP. MS closed it supposedly due to driver issues.

 

[dengamle]

I think you can actually compile kernels in Linux to support more RAM, but I think it's the equivalent of PAE in Windows.

PAE is not someting Microsoft has invented, it is something in the CPU. So it is actually called by the same name in Linux

 

[arson94]

ha yea i probably could have said that differently. For PAE, doesn't the northbridge on your motherboard also have to support it in conjunction with the CPU?

 

[dengamle]

Yes, the extra address pins on the cpu also have to be connected to something to be useful. Most modern boards today supports more than 4GB plus memory remapping, so it is not so much a hardware problem anymore that some 32bit OSes don't support more than 4G.

 

[grieve]

looks like im not needed here... you boys have this under control.

 

[gamecrazychris]

I have a Lynksys wireless router in 64bit Vista, just google around for a few minutes and you'll find some 64bit drivers.

 

[OS43]

I have a Lynksys wireless router in 64bit Vista, just google around for a few minutes and you'll find some 64bit drivers.

Its for the adapter, not the router. WUSB300N. Ive spent hours on google searching. The only option is *extremely* buggy drivers that windows update finds from some other company.