Because you would then have to fetch and compile any proprietary drivers manually. Not necessarily more work, more a matter of preference.

Just reuse your config file from the boot directory to your kernel directory and compile as is. Obviously, that means you will still have all the unneeded modules but at least you will have working kernel. Then you can tweak it a bit at a time if you feel like it.

Do you mean "compile your own kernel"?

Well, it's a matter of selecting the correct drivers as[*] in menuconfig. There are only two things that you need to boot a system usually: the driver for your chipset so you can access to your HDs, and the driver for the filesystem of your root partition (ext3/2, reiserfs or whatever you use).

The rest can wait, and it's a matter and trying, recompiling and rebooting. Less urgent stuff.

Installing gentoo is a good way to learn the internals of these things. Using the handbook and the manual installation of course, the livedvd graphic installer never worked correctly, and you wouldn't learn anything from that anyway.

This is a good way to get it working quickly

Why does the video driver have anything to do with how much ram is recognized?

I compiled linux 2.6.27.7 from source from http://www.kernel.org/ to my Debian Lenny/Sid distro.
It works fine except, I have 4GB ram and an Intel Core 2 Duo CPU E4600 @ 2.40GHz. But only 2.3 GB of ram shows up.

ocelot:/home/john# lshw -c memory
*-firmware
description: BIOS
vendor: Phoenix Technologies, LTD
physical id: 0
version: 6.00 PG (03/05/2008)
size: 128KiB
capacity: 448KiB
capabilities: isa pci pnp apm upgrade shadowing cdboot bootselect socketedrom edd int13floppy360 int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer int10video acpi usb agp ls120boot zipboot biosbootspecification
*-cache:0
description: L1 cache
physical id: 8
slot: Internal Cache
size: 32KiB
capacity: 32KiB
capabilities: synchronous internal write-back
*-cache:1
description: L2 cache
physical id: 9
slot: External Cache
size: 2MiB
capacity: 2MiB
capabilities: synchronous external write-back
*-memory
description: System Memory
physical id: 18
slot: System board or motherboard
size: 4GiB
*-bank:0
description: DIMM
physical id: 0
slot: A0
size: 2GiB
*-bank:1
description: DIMM
physical id: 1
slot: A1
size: 2GiB
ocelot:/home/john# free
total used free shared buffers cached
Mem: 2320232 2057860 262372 0 305576 930196
-/+ buffers/cache: 822088 1498144
Swap: 8305564 0 8305564
ocelot:/home/john#

Why? I compiled a 64-bit AMD64 kernel.

ocelot:/home/john# dmesg
[ 0.000000] Initializing cgroup subsys cpuset
[ 0.000000] Initializing cgroup subsys cpu
[ 0.000000] Linux version 2.6.27.7-hou2.2-02.jmc64 (root@ocelot) (gcc version 4.3.2 (Debian 4.3.2-1) ) #1 SMP Tue Nov 25 09:21:12 CST 2008
[ 0.000000] Command line: root=/dev/hdb1 ro vga=792
[ 0.000000] KERNEL supported cpus:
[ 0.000000] Intel GenuineIntel
[ 0.000000] AMD AuthenticAMD
[ 0.000000] Centaur CentaurHauls
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] BIOS-e820: 0000000000000000 - 000000000009f400 (usable)
[ 0.000000] BIOS-e820: 000000000009f400 - 00000000000a0000 (reserved)
[ 0.000000] BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
[ 0.000000] BIOS-e820: 0000000000100000 - 000000008fee0000 (usable)
[ 0.000000] BIOS-e820: 000000008fee0000 - 000000008fee3000 (ACPI NVS)
[ 0.000000] BIOS-e820: 000000008fee3000 - 000000008fef0000 (ACPI data)
[ 0.000000] BIOS-e820: 000000008fef0000 - 000000008ff00000 (reserved)
[ 0.000000] BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
[ 0.000000] BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved)
[ 0.000000] DMI 2.4 present.

I don't know what those BIOS-e820: lines mean.

Cheers,
John