The F2 key will get you into the Phoenix BIOS. (On my revisit in December 2018 I realise I meant press-and-hold. Random presses as it started up didn't seem to work).
Unfortunately for me when I got my X90L in 2011 I found that the BIOS was password protected and I wasn't able to get into it. You can read about how I eventually sorted that problem out under the Password tab.
If you find your X90L is password protected it is hopefully by the default Wyse password of Fireport. If not go to the Password tab and scroll down to the bottom.
The BIOS is fairly conventional with a limited range of settings. Going to the 'Boot' screen brought up:
1: IDE 0: 1024MB ATA Flash Disk-(P
2: PCI BEV: Realtek Boot Agent
3: USB HDD:
4: USB FDC:
5: IDE CD:
6: USB KEY:
After plugging in a USB card reader with 2GB Compact Flash card in it with the Wyse XPe update software for the X90 installed on the card the display changed to:
1: IDE 0: 1024MB ATA Flash Disk-(P
2: PCI BEV: Realtek Boot Agent
3: USB HDD: Generic STORAGE DEVICE
4: USB FDC:
5: IDE CD:
6: USB KEY:
...and finally I also plugged in one of my 1GB USB pen drives with Tiny Core 9.0 on it:
1: IDE 0: 1024MB ATA Flash Disk-(P
2: PCI BEV: Realtek Boot Agent
3: USB HDD: Generic STORAGE DEVICE
4: USB FDC:
5: IDE CD:
6: USB KEY: USB2.0 FlashDisk-(USB 2.0(R/F)F
The Xn0L runs Windows XPe SP2. Mine came with an unknown password set for the Administrator's account and auto-logged-in as the user User with User's password set to User.
Luckily it easy to reset the Administrator's password - or at least it was in the way mine was configured.
From the auto logged on user:
At this point the hack is only temporary as the 'write filter' is in place and any changes you make are just held in RAM and not written back to the flash. You need to log out and log back in as the Administrator using the password you've just set. Holding down the Left-Shift key when you logout disables the auto-login feature and brings up a conventional "Welcome to Windows" box with an invitation to press Ctrl-Alt-Delete to login. Having logged in as Administrator double-click on the FBWF disable icon to turn off the write filter.
The system will reboot at this point and you'll back to square one. However, as you go through the steps outlines above, this time the new Administrator password will be written to flash.
You can also take this opportunity to make other changes to the system - such as setting the network details for your local wireless network.
Once you're happy with the changes double click on the FBWF Enable icon to turn the write filter back on.