The 2.4 kernel changed the kernel start address from 0x310000
to 0x810000 to make room for the Wildfire's larger SRM console.
Recent consoles on Titan and Marvel machines also require the
extra room.

If you're using aboot 0.7 or later, the bootloader will examine the
ELF headers to determine where to transfer control. Unfortunately,
most older bootloaders -- APB or MILO -- hardcoded the kernel start
address rather than examining the ELF headers, and the result is a
hard lockup.

Say Y if you have a broken bootloader.  Say N if you do not, or if
you wish to run on Wildfire, Titan, or Marvel.

This option is required for IEEE compliant floating point arithmetic
on the Alpha. The only time you would ever not say Y is to say M in
order to debug the code. Say Y unless you know what you are doing.