Hardly topical in this Access database product discussion group, and
"average" is hardly meaningful. However, if you want to know what is typical
for a state-of-the-art desktop motherboard, I say 8 Gig. For laptop
motherboards, 4 Gig is typical.
It probably won't be long before 8 Gig laptop motherboards are common.
Stay tuned. In a few months, the answers will be different