I just tested out my new box with Slackware, and it worked fine, but since I intend to use it for gaming, I tried to slap in a copy of XP.
The thing is that when it's installed, I just get "Error loading operating system" when booting. Since it came loaded with XP, the only cause I can come to think of is that Microsoft, in their stupidity, didn't feel it necessary to wipe the MBR when installing XP. Am I right? How do I fix this as fast and as conveniantlly as possible?

I've tried reformatting/repartitioning X number of times now, and I'm getting weary...

And oh, I'm not turning my back on Linux, I still run a server with Lunar Linux on it :P

relax, now follow these steps:

1- Insert The Windows XP CD and do not start the installation rather go to the recovery console, by pressing 'R', when asked.

2- In the recovery console, I believe type:
(but check help there by typing help, It's been long since I've done it)

3- I believe there was one more command, I do not remember but it starts or ends something like
BOOT
check help, there are jsut a few commands supported so it wont be difficult to find.

4- Then Install XP, you'll be able to start XP only initially, but with Slackware CD2, which is a live CD you can chroot to your root, and then lilo to reset the boot sector, but be sure to edit the lilo.conf file so that you can start both linux and windows.

Just tried it, doesn't work... I'll try again though.

I might have found a solution here.

I'm holding my thumbs.

I'm a bit confused. Are you saying that you installed Slackware then installed XP? If so thats your problem. Reinstall XP first, setting a partition up for windows and leaving the rest of the disk unpartitioned. Then install Slack on the remaining un-partitioned space.

Windows doesn't play nice when multi-booting other OSes. As such if you install XP last it will hijack your MBR and replace any bootloader their with it's bootloader, which of course will only boot Microsoft OSes.