Xenium chipped Xbox help

So I found and bought a cheap original Xbox in a charity shop, 'modded but not reading discs'. Turns out it was just the usual sticky tray prob, it reads discs fine when they're in the machine. It still has a stock hdd. Anyway, when it boots up, there's a brief screen that says 'Xenium', then the usual Xbox dashboard. It plays backups no prob, but I can't figure how to get to the modchip menu. Google didn't help much and I have no idea which version of chip it is. Of course I'd like to install a custom dashboard and upgrade the hdd (using Hexen or whatever) but without knowing anything about this modchip (or modchips in general!) I'm reluctant to risk messing up a working xbox. Any advice, please anyone?

Never had a xenium myself but there probably isn't a modchip menu.

I've had a few chipped consoles over the years...I've only really used slayers to format/setup new HDD.

Am I right in thinking that with a modchip, I can just swap in anew hard drive and run either the Hexen or Slayer dvd in the xbox to set up and use the new hdd instead of cloning the old one or using a pc?

Yep, but as I said I've only ever used slayers myself.
No need to clone just format and setup your HDD how you want. Thing is with the last slayers pretty sure some progs will still need to be updated after setup anyway.

Well I used Hexen to install a 320Gb hdd, working fine except there's only 250Gb available space. I had assumed the hdd was wiped before I bought it (used). Could the problem be that there is a Windows or whatever partition still on the drive, so only the remaining space was formatted by the xbox, or did I screw up somehow? Should I take it back out, format and wipe it on my pc, then re-do the install from scratch?

I haven't used Hexen, but I can't see any programs bothering to keep old partitions. There's probably just a bit of unpartitioned space, use xbpartitioner to sort it out.

Slayers will use all the drive, I've formatted and setup 320GB drives using it before.
Never used hexen so idk what it's doing.


If you use slayers v2.7 you shouldn't need to use xbpartitioner for a drive larger than 137GB.

Yea I used Xb partioner, but I only got options for 250gb, that's when I spotted the prob. Maybe I'll re-do it with Slayer's, only prob there is I've ran outta blank dvds. What's the likelyhood of it working from cd-r? I've heard that some disc drives won't accept them.

Itried a cd for Slayer's, loaded no prob. I followed instructions to format and install the hdd. All done now. BUT I now have just 123Gb instead of 320! WtF?!!