EggXpert

I'm building a new computer and tried installing vista home premium about 3 times before I sent back the motherboard and other parts for replacement. I did this because the new system told me I had hardware problems and would not load the OS. When I receive the new parts from Newegg will I still be able to install Vista 32 bit system.  Newegg didn't know and they will not take back the software because it was opened. Also on another thread I was told to get the 64 bit version because I'm going with 4 gigs of RAM.  Is this necessary and why?

First Point:

You should be able to install Vista.  The worst thing that will happen is that you will have to call Microsoft to activate it.  No big deal.

 

Second Point:

If you are going to go with any more than 3GB of RAM, you should get a 64 bit version.  If you stick with a 32 bit version, you will only be able to use about 2.5 - 3GB of what you install.  This has to do with how the operating system addresses and handles memory.  32 bit versions are limited to ~3GB, while 64 bit versions are limited to around 128GB. 

Case in point, I triple boot in Linux (32bit), XP Pro 32bit and Vista Business 64bit.  Even though I have 4GB of RAM on my system, the Linux and XP operating systems can only use about 2.4GB (I have a graphics card with 512MB or RAM on it, which also must be addressed by the OS), while the vista version can see it all.

That brings up another point I should mention (enough points for you yet? :p).  The memory on your graphics card must be handled by the OS, too.  So, if you have, say, an 8800GT like I do with 512MB of RAM, that will lower the overall system memory that the operating system can use by that much, dropping you from about 3GB to about 2.4GB.
 

Yea plus if you didn't register it online or over the phone you could use the a million times. Microsoft only knows when you use the key when it is registered through Microsoft.

Which, unless you have a hacked version (which I strongly advise against), you HAVE to register it within (I believe) 30 days or Vista will lock you out.

Guardian:

Second Point:

If you are going to go with any more than 3GB of RAM, you should get a 64 bit version.  If you stick with a 32 bit version, you will only be able to use about 2.5 - 3GB of what you install.

I thought that 32-bit versions could use 3.25gb of ram... not 2.5gb.... 

It varies from OS to OS

Oh... So for XP 32-bit it can support 3.25... but for Vista, it can only support 2.5gb?

Perhaps...I'm not 100% certain...from what I've gathered it varies from OS to OS

As long as you have a minimum of devices connected you should be able to get up to about 3.8gb of ram.  The theoretical limit for a 32 bit system is 4gb however that would be with nothing hooked up to it, and chances are you are gonna want a hard drive, maybe a optical drive, maybe a video card (even integrated graphics counts) so reaching 4gb is not really possible on 32bit.  Depending on your OS you can get a lot more from a 64 bit os.

XP 64 supports up to 128gb as does Vista Business, Ultimate, and Enterprise, while Vista Home Premium supports up to 16gb and Vista Home Basic supports up to 8gb.  However 64 bit in theory can support a lot more than 128gb, I believe the 64bit theoretical max is 17,179,869,184gb which is a whole lot of headroom for the future. 

Indeed, which is why all the OSes you see installed in the near future will be 64bit.  Plus, if you have a 64bit processor (pretty much any processor from the last few years), 64bit will run faster, even without a ton of RAM.

Wow... I didn't know that.