PC only reads 3.5 gigs on 4gigs of RAM

[chris1784]

its running a 32 bit vista for OS. Could that be the problem?

 

[gramps]

Only 64bit OS's can use more than about 3.5Gig RAM - something to do with adressing I think.

 

[huron]

From what I understand (which may not be enough, and therefore I am interested in hearing what people who know more would say) is that 32 bit systems have a maximum of 4GB of RAM allowed.

From this 4GB, the OS and hardware use some of the RAM, so you never see the full 4GB. I guess this is why 64 bit has some advantages (a much higher theoretical limit for RAM - I think it supports at least 8GB now, but I think the limit is well beyond this - I believe I read the theoretical is 128GB max, though is not supported by harware).

I am debating this problem myself - I don't really want to get Vista, but think I may have to to enjoy DX10 graphics. And if I do decide on Vista, should I get the 64 bit (or do I get XP pro, and then do I get the 64 bit version).

Anyone have suggestions on these problems too?

Sorry if I changed/hijacked the thread - hope that answered your question about the RAM too. If not, hopefully someone else will be able to elaborate and fill us both in.

 

[croc]

its running a 32 bit vista for OS. Could that be the problem?

Most 32 bit OS's will have this issue. XP will, and quite a few distros of linux 32 as well.

Anandtech did a couple of excellent articles on this, here is the link to part 2...

http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=3044