Hi William, welcome aboard.
I'm afraid I don't understand your question properly. Could you expand please?
Lots of people didn't like MVP3 boards in general and the 503+ in particular, but I always loved them. Our three Athlons aside, all our other machines are K6-III+ and VA-503-based. I make no claims to any especially detailed knowledge of them, but if it is likely to help I probably have as much hands-on experience with VA-503 main boards as almost anyone. I have no idea how many 503-based systems and upgrades we sold, but it was certainly over a thousand, and - believe it or not - we still have a few brand new 503s in stock for repairing older systems.