Different versions of Windows 7 have different memory limits

[javajolt]

Win 7 Ultimate caps out at only 192GB

is trying a bunch of new things with Windows 7, and one of the many of these new things is setting the upper limit on your system memory according to which version of Windows 7 you are running. This was done for Windows Vista, but is even more stratified now. Don't worry though -- the limits seem pretty reasonable.

Here they are, for the 64-bit editions (32-bit editions will all be capped at the standard 4GB):

• Starter: 8GB
• Home Basic: 8GB
• Home Premium: 16GB
• Professional: 192GB
• Enterprise: 192GB
• Ultimate: 192GB

192GB of RAM. Whew. That'd be pretty zany.

However if Windows 7's lifespan is half of XP's, then it isn't too hard to imagine many users coming up against the 8GB and 16GB limits. Actually with DDR2 selling for as low it has been recently, 8GB of RAM doesn't even seem all that outrageous anymore.