upgrade memory readynas ultra

That's a good motherboard, I have the GA-P35-DS3P in this desktop. You are unlikely to find an add in board for your desktop with better performance than the one already on you MB.

Transfer speeds depend upon a number of factors, and the file size and type is one of them. One of the reasons I suspect I was able to transfer a test file from my desktop faster than I could transfer the same file to the desktop was that my Avast! Anti-Virus was actively scanning the file during the transfer to process. (It gives an indication when it is scanning a file.)

You can try increasing the memory on the Ultra, but be sure to do a memory test as an incompatible memory chip does not always make it presence known on a ReadyNAS as it does on the desktop. There have been many posts about memory problems cropping up days or weeks later and damage to the data files is a real possibility. One of the reasons that Netgear does not recommend memory is that some memory manufacturers have been making significant modifications to the chip supply, number of chips, etc. and not changing the model number on the module. The are cases noted on the NV+ list where a module with a particular number was compatible and the manufacturer changed the module but not the number and it is not very incompatible.