Just a quick update... After 3 emails to the seller, no response. Great customer service! I didn't want to solder the jumpers on the chip in case it didn't work and the seller claims I "damaged" it. I took apart my A2500 which has 3.1 and found an Escom 40 pin ROM chip, I removed it and put the 42 pin EBay chip in the 2500 and it worked. So I kept the Escom chip for the 500 and ordered a socket so I could do the soldering on it instead of the ROM chip in case I swap things around again :-). Thanks to everyone for the links and info about jumpers.