1. I got 4G ram installed on my IBM X61 Laptop, with Ubuntu 9.04 Jaunty Desktop for i386 installed.
2. I need to use my whole 4G of ram bcoz I always has about 400 tabs opened in my Firefox.

All 32bit system can allocat only 33.5G of memory.

X61 uses Intel chips and VGA chip, which is some kind of shit.
Want to improve the xorg's intel driver, you got to install the latest kernel and driver, with UXA mode enabled.
Then, you might get glxgear score about 700~800fps, nice.

Now here comes the problem.
Kernel's PEM conflicts with UXA, and makes the UXA's advanced GPU memory handling unusable.
So I can only have two choice:
1. Use generic kernel and better graphic performance, but only 3G of ram. But my memory is always full.
2. Use server kernel, got whole 4G of ram, but the glxgear score is only about 220fps. Sucks!

With 64bit system, the kernel can natively support to 64G of ram, so I can use 64bit generic kernel with whole my 4G of ram and enjoy the 800fps glxgear score. That's Great!

BUT, How To Install a AMD64 (64bit) Kernel on my i386 (32bit) System?
I did some google search but still find nothing really helpful...