I have a computer (xps420 with 4GB of RAM) that I installed the 32 bit version of Win7 but Im thinking about downloading and trying the 64-bit version. Can I do that and is there really a big benefit in doing it? From what I understand having read about 32 bit vs 64 bit I am not fully utilizing my RAM with the 32 bit version. Is this correct? Any help is appreciated!

Basically correct.The 32Bit OS's can access 4GB of memory in total, but that includes all ofthe reserved memory spacededicated to or used by hardware, especially your video card. For example if your video card has 512MB of video RAM on it then the amount of system RAMthe 32Bit OScan use is something less than [4GB - 512MB] =3.5GB. That's only a rough figure because thereis memory space devoted to other hardware in the computer as well. The 64bit OS will be able to use all of your systemRAM and then some, but you'll need to find some 64bit applications before you'll see anysignificant performance increases.The performance index scores on my PC were nearly identical for 64bit and 32 bit Windows 7. There was a 0.1 point increase in both theRAMand CPU scores with the 64Bit OS. The 64bit version will require different drivers for all the hardware as well. I found that there were more of my own devices that did not have 64bit drivers availablethan with the 32bit version of Windows 7.

Ralf is correct, 32 bit can use about 3.5 Gig of memory (RAM).With 64 bit you can put in more memory IF your motherboard will support it. Most of the new motherboardsI have seen can handle 8 Gig.Also, older programsmay not run with 64 bit.Some older ones that I know that have problems are Outlook, Quicken, Quickbooks.Drivers for some older hardware may not be available.So go to the manufactures web site, check for drivers and check out the specs for any older programs you have and see if updates are available.The good news is that 64 bit is actually usable now vs. a few months ago when it was nothing but a large headache.Bob

if you're not sure if your OS can run 64-bit, you can check at the Windows Experience Index then "View and print detailed performance..."It will say there if you'll be able to run 64-bit.example: 64-bit YesSample is this:Performance Information and Tools<--- image linkThe Benefit in doing it is if you're using more than 3GB of RAM then yes, you will benefit from it. If not, 32-bit will suffice.

It appears that is just telling you that you are running 64-bit OS, not that the computer is able to run it. So if you have 32-bit installed then it will say 32-bit, not 64-bit capable.

Yes memory allocation is as explained by Ralf G above, coming to Windows 7 beta from Vista 64, I decided to go with the 32bit for Beta and then swap back to 64bit Windows 7 at launch

Just so you know, x64 has come a LONG way. I have been using it pretty much exclusively for over 2 years (starting with XP x64) and **almost** all applications will install and run on Vista x64 and so far on Win7 x64 (Including Outlook 2003 and Outlook 2007). Do not be scared of it. It's come a long way! David Dracoules

I started using 64bit OS with Vista Beta2. Today i use x64 Vista both at work and at home. Games can sametimes a little bit tricky, but i have got nearly everyone to work.For the 32bit Apps, WOW is used, (Windows-On-Window).For my part i won't go back to 32bit OS anymore, especially with this low prices for RAM. If your mainboard support it, go for 8GB and 64bit OS.RegardsHarald

Hi Bob,I have never heard that Outlook can not run on 64-bit. Which version of Outlook do you especially mean?Peter Forster, MVP Virtual Machine, Austria

Peter,Outlook 2000 does not play well with Vista 64, so I would guess it will be problematic with 7.2003, and 2007 are fine.Bob

Hi Bob,I see. I have installed Outlook 2000 on Windows XP 64-bit since years without any problems, so I thought it will also run on Windows Vista 64-bit, but never tried!Peter Forster, MVP Virtual Machine, Austria

Outlook 2000 is 9 years old and has been superseded by newer versions several times. Time to upgrade. :)