The "home" page for HP/Compaq/DEC Alpha systems' firmware now seems to be

     http://ftp.digital.com/pub/DEC/Alpha/firmware/

Perhaps the appropriate name for your machine on that page would be 
"Digital Server 3300" in which case its firmware is available at

     http://ftp.digital.com/pub/DEC/Alpha/firmware/readmes/as800.html

so apparently it uses the same firmware as the AlphaServer 800.

According to the list at the bottom of this page

     http://www.netbsd.org/Ports/alpha/

the AlphaServer 800 and Digital Server 330x systems have been able to 
run NetBSD since version 1.4, so I'm sure they'd both run Tru64.  (In 
fact I've just noticed

http://ftp.digital.com/pub/DEC/Alpha/firmware/readmes/v6.2/alpha800/fwreadme.txt

says firmware version 5.8 is qualified to run Digital Unix V5.0 and V4.0G.)

I expect there's an option somewhere in the ARC console the machines 
you referred to are using now to switch to SRM instead.


Ray