The Winchester core is newer, and is theoretically better. Some people ran into problems with it, though. I just bought an A64 system a few months ago and researched the problem somewhat. What I found leads me to believe that:
A) There may have been a bad batch in the initial release (if true, it's fixed now)
B) Most people's problems stemmed from a bios that didn't recognize the CPU properly. A bios upgrade generally fixed that problem. What ticked a lot of people off is that since it was a brand new technology most folks didn't have a spare A64 CPU laying around to use during the bios flash. Those poor souls had to take their board into a shop and pay big bucks to have it done there, borrow a Newcastle core CPU from a friend to use during the bios flash, or mail their bios chip out to have the flash done elsewhere.
As long as you make sure that your MB supports the Winchester core you should be just fine.
Comments
A) There may have been a bad batch in the initial release (if true, it's fixed now)
B) Most people's problems stemmed from a bios that didn't recognize the CPU properly. A bios upgrade generally fixed that problem. What ticked a lot of people off is that since it was a brand new technology most folks didn't have a spare A64 CPU laying around to use during the bios flash. Those poor souls had to take their board into a shop and pay big bucks to have it done there, borrow a Newcastle core CPU from a friend to use during the bios flash, or mail their bios chip out to have the flash done elsewhere.
As long as you make sure that your MB supports the Winchester core you should be just fine.