Rebuilding a Dell 2300 ... keeps shutting down during Windows installation

Anyone:

I just broke down my 2300 Dimension.
Pulled the old hard drive. (nothing important there, crashed anyway)
Replaced the power supply with a 450w (new)
Installed 2 new Seagate hard drives and a new dvd rom.
To start, I setup only the master drive to load the OS (Windows 2000 pro) as
well as the floppy, and the original cd / rw
During the initial stage of loading the OS, the system shuts down as soon as
it gets to "Loading Windows".
Exchanged the power supply with new ones ... 3 times!
Same issue.

Jumped the CMOS ... (again) and started over.
Checked the CMOS and set the 1.8 cpu to clock at 10 (default, I think)
No other changes were made.
I'm stumped

Anybody got any ideas as to what is going on?

Thanks...