Memory error on K8NF4G-SATA2

Hi.
I hope this group is "general" mainboard.
If not. Sorry.

Assembled a computer with the following parts:
Asrock K8NF4G-SATA2
Elixir 512MB PC3200 PARTNo M2U51264DS8HC3G-5T
Unknown PC2100 256MB module.

The problem:
No signal to monitor when using the Elixir RAM module.

At first the Elixir module worked.
I started the computer for the first time entered BIOS and changed the
memoryspeed to 400 since it was set to 333.
Began installing Windows... after a while came the dreaded bluescreen.
Restarted the computer but now I had no video.
After trying various things like clearing CMOS and eliminating broken
cables and such, I gave up and tried another mem-module. This one
worked just fine.
Installed the Elixir as second module and everything worked.
Bios is reporting 256+512MB at 266MHz
(haven't tried a new install though)

What's wrong??
Workarounds? (except for the obvious: using the slower module and
buying a new module)

since you now have it running again, i would pull the pc2100 place the pc3200 in the the first slot and reboot. if it posts, then i would run memory86 on the 512 stick and check for errors. i assume it's going to be running 333. leave it that way.

http://www.memtest.org/

let us know how it goes.

another handy program that may help later is:

http://www.cpuid.com/cpuz.php

ud