32-bit OS and 64-bit CPU

This was probably discussed zillion times but keywords are too floppy to find the correct link on Google.

Okay, basically I need a brief idiot’s guide on what are the advantages of having 64-bit CPU but using 32-bit XP OS? Is there at least any leak that processes can take advantage of of using 64-bit processing?

There aren’t many advantages to using a 64 bit capable CPU to
run a 32 bit OS. The latest 64 bit CPUs from AMD and Intel are
based on the latest technology, so they will usually run 32 bit
code faster than older 32 bit processors. A lot of the new 64 bit
CPUs are dual or quad core which can be a big advantage if
your OS supports multi-processing.

I have found that installing a 32 bit OS on a 64 bit machine is
generally easier than installing the 64 bit version. 64 bit drivers
are not available for a lot of hardware. A lot of software is only
available in the 32 bit version. This can lead to problems when
you need to mix and match 32 and 64 bit software. For example:
running a 64 bit web browser with 32 bit plugins like Flashplayer.

Currently running 32 bit Ubuntu Linux on this AMD-64 laptop
and 32 bit Debian Linux on my AMD-64 desptop PC.

I recently went to Windows XP x64 on my laptop that has 1 gig of RAM, Turion MT-37 processor and a 7200 rpm hard drive. While there aren’t many programs written for 64 bit it will run darn near any 32 bit program out there. One advantage I see with running XP x64 is memory and disk transfer rates are higher and the laptop definitely has more “snap” to it than with 32 bit XP even on 32 bit programs. I haven’t found any issues with drivers as my laptop included them on the disk supplied with the machine.

So far I am pleased with the results of going to XP x64 as there is a noticible improvement in performance. Don’t expect miracles though. Some things like many of the Powertoys etc. don’t work with XP x64 but when you find an x64 program that works for you it pays performance dividends. While I can see 64 bit OSs are not for everyone I find it works for me so far.

I remember a few years ago when amd just came out with the amd64. Some articles said that even thought there was no software that ran 64bit at the time, the amd64 still ran faster than a comparable 32bit processor. I still think this is true, even though you aren’t taking full advantage of a 64 bit processor with a 32 bit os, I still think it handles some overhead better.

It’s the same with a dual core. Even though most software isn’t written for it, I have a dual core laptop, and desktop. The biggest difference is that when I’m running a high cpu process, I can still run / open other windows with no hit on performance. I always had the OS hang with a non dual core process.

This is just my observations and opinion.

As far as I know, there are no “sneaky” ways to use the 64 bit extensions in 32 bit, though some functions on a 32 bit CPU are already 64 bit or more, FPU, SSE and other subsections may work with 64 bit operands.

The only major plus, is that CPUs with 64 bit capability also tend to support the NX / XD bit, for hardware data execution prevention. I’d recommend using the “optout” method, where DEP is applied to all system components and applications except those where an exeption has to be made. Ideally, replace all applications that require exeptions and enforce DEP completely. It is a pretty robust defence against many known or unknown attacks that rely on buffer overflow or similar vulnerabilities to cause execution of code.

The main advantage of a 64 bit OS, is in working with either excessively large application virtual sizes, or with memory larger than 3GB.

hi this is interesting I cant help your problem but you may be able to help me. can you tell me how to find out if mycomputer is using 32 or 64bit as I need some drivers and dont know version to get untill i can answer that basic question. Probably seems childish to you? Yes i need help and thanks in advance for any support you may be able to give me.