BleepingComputer.com: PCI Express 2.0 x16 Video Cards

No, in 32-bit land you can have a max of 4GB however not all of that will be visible due to memory addressing. Approximately, 3.5GB will be visible. Once you go 64-bit, all of your memory will be usable and you can expand on it further by going to 8GB.

Of the three 4GB kits I linked to above, any thoughts on if one kit is better than another (throwing cost aside for the moment)?

All have the same timings and latencies, all have heat spreaders and are from good companies. The second one down saves you the most money off the MSRP.

Your not missing a thing. The most a 32 bit windows xp OS will read is 2 gigs. A while back I didn't even know about this and I stuck 5 gigs into my comp and I checked in my system specs and all it would ever say was 2 gigs. So be careful.

PlagueRages, on Dec 6 2008, 02:09 PM, said:

That's not entirely accurate. The 32-bit OS can handle 4 GB of RAM. However, due to memory addressing, the amount is lower. Depending on what hardware you have installed, a 32-bit OS will read approximately 3.5GB to 3.0GB. Below is a link to explain it in Windows.

Microsoft - The system memory that is reported in the System Information dialog box in Windows Vista is less than you expect if 4 GB of RAM is installed