1- Plug in ur USB device BEFORE powering up.
2- Put USB drive on USB hub
3- Power UP
4- Enter BIOS through F2
5- Go to the "Boot" main menu
6- Left to the Harddrive you will see a "+" (plus" mark).
7- With the arrows select it (should be white).
8- Hit enter and voilą
In case of USB DVD/CDROM the methord is almost same, just change the boot option to cd rom
I did not want to put up new thread and leave the old one hanging around.So edited the initial thread . The problem was lack of documenation & acers ignorant support engg . So i'm sharing exp heree which might help others
***** OLD Thread Below Please ignore it *******
In most ACER laptops i have seen "BOOT FROM USB" missing , Which is a must nowadays
ACER TRAVELMATE 2300
ACER TRAVELMATE 4000
ACER TRAVELMATE 4500
ACER ASPIRE 1680
ACER ASPIRE 1410
These are the models i know so far..if your model does not support please add it here
Boot options available in ACER laptops ( No USB, No PCMCIA)
2) Hard disk
4) Network Boot
I think we should form a group and ask ACER to release new Bios update which supports "Boot from USB" Funtion
I have not seen any one complaining this so far . So thought of putting up a thread
If your are intrested please post your opinions
-Venombite- Have this issue been reported before , may be no one cared to check
Actually, you may want to check to see if you have an option in the BIOS for Legacy USB. If so, you have to enable this and reboot back into the BIOS. After the reboot, it'll give you an option to boot from USB (have to have the USB device connected at the time). I'm not sure if Acer has this option, but it's a very common item in HP, Toshiba and other brands.
One catch, when you enable this option, you effectively disable USB 2.0 capabilities in Windows. You can still operate at USB 1.1 speeds (12Mbps), but that's a MAJOR drop from USB 2.0's 480Mbps speed. I guess if you're booting from a floppy, you technically don't need USB 2.0 speeds since there's probably something wrong with your OS. 
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