Hello, I recently acquired an old Mac Pro 1,1 and have been trying to update it to version 2,1 in order to facilitate better processors, but after trying nearly everything I can think of I am still unable to perform the update. As I have done so much it will be neater if I post it in bullets: Firstly I tried performing the update using the Firmware Upgrade Tool provided on Netkas. The Mac Pro was running 10.6.8 with the supplied hard drive in bay 1, ATI Radeon 2600xt and 2GB of stock RAM. The tool made the RAMDisk successfully and prompted a shutdown and firmware upgrade procedure. The initial steps of the upgrade went well, but upon getting to the update screen with the progress bar for a split second the machine just restarts and boots into the OS. Next I tried with 10.7.5, performed SMC an PRAM reset but now I got stuck at the RAMDisk creation with Error 5530 while downloading the needed content. I also tried downloading the EFI 2,1 from the Apple website and mounting it alongside, but the outcome was the same. With both operating systems I also tried switching the RAM configuration, even changing both RAM trays with the ones from a different Mac that has successfully performed the update. I also tried switching the optical drive and graphics card for a HD4870 that were also used in the other system and worked well. I tried inserting a different Apple HD with 10.9.5 and got past the Error 5530 but got stuck in the same spot as with 10.6.8. Finally I tried doing an ASD test that came up with no issues. I also tried restoring the firmware with the Firmware restoration CD 1,4 but could not get the machine to start reading from the CD (it just booted into the OS). At this point I am running out of components to switch out and configurations to try, and so am asking if someone has encountered this issue or would know what the next logical step in my troubleshooting would be.