I'm just wondering why it would matter to remap the hardware above 4gb if Poster only wants to recognize 4gb?
Sorry, just trying to learn.
A problem should be that he's using 32bit. Even if his board supports more than 3gb, A 32bit OS won't recognize more than 3gb (just a tiny bit more in some cases). If this isn't resolved, it wouldn't matter any other problem his OS has and fixes, his 32bit OS still won't recognize it.
No, a 32 bit operating system recognizes all 4 GB. The problem is that your hardware also requires memory addressing.
So lets say you have a 32 bit OS and 4 GB of RAM and your hardware needs 800MB of memory addressing. Since your OS can only address 4 GB and 800 MB is already used for hardware, you only have 3.2 GB left for memory. Your OS can't use memory if it can't address it.
Now, a 64 bit OS can address a lot more RAM, BUT often motherboards will still allocate the hardware memory mapping inside the first 4 GB. So if you have 4 GB's and a 64 bit OS but the hardware is still mapped from 3.2GB point through 4 GB's, you will still only have 3.2 GB's of usable ram.
This problem is usually fixed by a memory remapping switch in the bios which will remap the hardware above 4 GB so it doesn't conflict with the RAM addressing. But not every board supports this function. If not, your 64 bit OS will still have trouble with hardware reserved memory just like 32 bit OS does.