CF-18 USB Boot " live ubuntu "

I have a CF-18 Mk4, and I am trying to get it to boot from usb. I made a Windows XP USB installation stick, and it works fine. I had a live ubuntu image on that USB stick that XP install is on now, and the live linux worked fine.

That was on a 1gb Sandisk cruzer U3 with U3 removed.

Today I went to make a live ubuntu USB stick with a 2gb sandisk cruzer U3 with U3 removed, and it wont boot. It boots fine on my work desktop, my acer laptop, but on the 18, I get one blink on the USB drive, and then nothing.

I've been racking my brain on this since 5:30 this morning. I just dont understand why the XP install USB works fine on the 18, and any other computer, but this other one with linux wont boot on the 18, but will on any other computer.

have used rufus, pendrivelinux usb installer, and winsetupfromUSB to try to get it to work, and nothing. I tried it as FAT16 and FAT32 just to be sure.

 

I added " live Ubuntu" to the title so Sadlmkr (Jeff) would see it , he knows this OS best.

 

Thanks. I did some more playing, and tried another thumb drive. It works on the other thumb drive, just not this 2gb. It just baffles me that the 2gb that wont work on the 18 works on every other computer I try, and the 1gb I have, same company and model, works but that 2gb won't

 

Does a MK4 have USB in the boot order?

Possible SD v.s. SDHC issue?

Linux is picky about formatting., but not much else.

G'luck.

Jeff