Question : Problem: How much ram can I install in a motherboard under Windows XP?

I have read several postings about users only able to see 3GB ram under Windows XP. Here is my question need a answer before I purchase:

I was given a new unopen ASUS P5B motherboard. The specs are here
http://usa.asus.com/products.aspx?l1=3&l2=11&l3=307&l4=0&model=1178&modelmenu=2

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Intel® Quad-core CPU Ready
LGA775 socket for Intel® Core"2 Extreme / Core"2 Duo / Pentium® Extreme / Pentium® D / Pentium® 4 / Celeron® D Processors
Compatible with Intel® 05B/05A/06B processors
Intel® Hyper-Threading Technology ready
Support Intel® next generation 45nm Multi-core CPU
Intel® P965 / ICH8 with Intel® Fast Memory Access Technology
4 x DIMM, max. 8GB, DDR2 800 / 667 / 533 MHz, non-ECC, un-buffered memory (can run 1066 MHz)
Dual channel memory architecture
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I want to purchase
-Intel Core 2 Quad Q9550
-Ram say I max it out at 8gb
-Plan to keep using Windows XP do not like Vista

1. From what I read, looks like Windows XP 32-bit OS will not see all that memory only 3BG or so. If I want to stick with XP then would installing 64-bit XP be correct for what I want to purchase?

2. What is Windows XP 64-bit? What I mean is if I installed the 64-bit version should I expect the applications I loaded on the 32-bit version to still work on the 64-bit XP install? Compatibility issues?

3. The motherboard I selected with the specs listed above if I ignore all that I read about the 3GB limit on the 32-bit OS would the ASUS P5B see the 8gb of memory if I foolishly installed WinXP 32-bit version?

"""" I am looking for answers to the above question for installing 8gb of memory """""

1. If I only installed 4gb of ram on this motherboard, should I just install the Windows XP 32-bit version? Or would I benefit from the Windows XP 64-bit to get the full functionality of the memory handling?

2. Having more than 4GB of memory a waste? I am a graphic designer but as I have read it seems that WinXP 32-bit uses on 2GB for apps. I am confused on how much memory to purchase and on what XP OS to buy 32 or 64 bit...?

I am a graphic designer using Adobe, Corel, other graphics apps and the system will host a mid-range express PCI video card so I need a powerful machine with lots of memory & processing power..Help

Answers to these question will help my confusion...


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What I used for Ref
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PCBONEZ:
Explaining another way:
Memory is 'addressed' by Windows.
Addressed means to assign an ID number to it's location. (just like your house).
32-bit Windows only allows 4 GB worth of addresses.
Some addresses are reserved for system (hardware) use and are not available to Windows.
The reserved adresses start at 4GB and are numbered down from there.
Memory addresses for Windows use start at 0 and are numbered up from there.
Where ever the numbers going up run into the numbers coming down is where Windows runs out of available adresses.
That point is usually near 3.5 GB but that depends on the system devices that need reserved addresses in that particular system.

SPARKMAKER:
The missing memory , do you mean ram or address space? They are totally different things.
If ram,--> it isn't missing just not used because it can't get address space that is already allocated to system resources(two devices can't share an address space)

If its Address space--> It is used by the
- System BIOS (including motherboard, add-on cards, etc..)
- Motherboards resources
- Memory mapped I/O
- configuration for AGP/PCI-Ex/PCI
- Other memory allocations for PCI devices

The differences you see are within these parameters , perhaps a different video card with more video ram, more PCI cards in one PC that the other.

Answer : Problem: How much ram can I install in a motherboard under Windows XP?

Windows XP (or any 32-bit OS) can only handle 3GB of ram, this is true.

Installing 64bit XP would work, but you may run into software or driver issues.  64-bit OSes require different drivers, so make sure everything in your system (hardware) would first be compatible.

As a graphic designer, having more than 3GB of RAM would be beneficial running memory-hungry apps with large document sizes.  Personally, I do my design work on a Mac because it has 4GB and handles running several design applications (Adobe Suite) MUCH better than a PC does.  But if you must use a PC, 3GB is a relatively decent amount of memory, but if you're doing LARGE file sizes (i.e. Banners, Large Posters, extremely high resolution files, etc), the more RAM you have the better your system will run.

If you're doing graphic design for websites, or smaller print work, 3GB of RAM will be fine.

Adobe, as far as I know, is going to be a 64bit application in CS4.  I do not believe they support 64bit yet, but that's not to say I've tried it or it will or will not work on a 64bit system.

I would be wary of future compatibility issues with Windows XP 64 bit, if you choose to go with it.   32bit programs SHOULD run fine in a 64bit environment, but will not take advantage of the 64bit architecture.

Me personally, I'd get the 32bit with 3GB RAM.