You can sorta turn your computer into a a MP 3,1 it just takes alot of work..
Remember the 5355 is not the end of the line for the 53 series Xeons..
Keep the computer as is play with it if it does what you need you'll spend less money in the end buying a knew mac pro..my 3,1 started life as a 1,1 and I have spent an unbelieveable amount of money gettin 1/2 to 2/3 of the processing power available in a single processor 2010 MP
I don't believe there is any way to make a 1,1 have the boot chime be followed by a boot screen on an EFI64 video card.
This means 1,1 and 2,1 are forever limited to 8800GT as best Nvidia card.
There may be software hacks to run a GTX480/580 but that is nothing like having them run "natively".
When I read the first post in this thread I was amused by the OP saying he had read reports of flashing a 1,1 into an EFI64 machine. There are of course no such reports. I have often marveled at the power of wishful or magical thinking. People hearing or remembering something they WANTED to hear or read, when in fact it was never said or written.
But when people say that it may be possible to turn a 1,1 into a 3,1, well now we know where maybe this guy "heard" or "read" these reports.
Last week I got an email from a customer who told me he would be getting an EFI64 Nvidia card for his 1,1. He believed that since he was installing some "64 bit Xeons" that he would soon have a 64 bit machine. The fact that he was REMOVING 64 bit Xeons to do his upgrade never crossed his mind.
I worked with a guy who was developing the 1,1 to 2,1 flash. We went to a great deal of trouble to extract the file from my 1,1. He was trying to find a way to run 3,1 EFI. The end result was that there was some component that changed, RAM controller maybe? In any case, the knowledge needed to combine the boot EFIs was beyond his abilities.
I'm sure APple could do it in minutes should they wish. They probably even HAVE a 64 bit EFI for our machines. But it won't be out in the wild until these are obsolete relics, if ever.
The 1,1 and 2,1 have many limitations. The fact that they are EFI32 is something we are stuck with. Yes, you can use Hackintosh boot schemes to make it think it is a 3,1 and run a 64 bit kernel. But at some point ask yourself what your time is worth. At some point in life you realize that spending umpteen hours fiddle fading with boot loaders just so you can avoid dropping $1K to upgrade to a 4,1 is silliness and a monumental waste of time.
If and when the 6,1 comes out, the prices on 4,1 and 5,1 will drop like a bird shot from the sky. Wait for then if you must. Add an SSD and some RAM, but trying to get EFI64 on one is a fool's errand at this point.