Can any advise if my old Mac Book 4.1 can run 10.6.8 ?
Yes, it will run Snow Leopard. See the link below for requirements and ordering info.
Mac OS X 10.6.8 will work with all Intel Macs that shipped with 10.6.7 or earlier and have at least 1GB RAM.
My Mac is running 10.5.8, Intel Core 2 Duo and 2.1GHz....so with your rersponse is it maxed out ?
Your computer can be upgraded to 10.6.8 and 10.7.5, but not 10.8.2.
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