Hi, I just thought I would put in my two cents on the matter. My guess is HP needed to find a way to make their product line a little more accessible to the low-end market and called upon AMD to provide them a cpu solution. That solution would appear to be the Sempron 3000+/3200+.
By having this cpu, both parties benefited. HP now would have a highly scaleable laptop without having to have two mainboard designs and AMD would be able to unload AMD64 that didn't pass 100% of the quality control. With the 1MB of cache in the AMD64 4000+, that makes for 2-8 times greater the chances for a bad die depending on which sempron and amd64 you are comparing. I imagine that it is very possible there is little wrong with these rebadged semprons except maybe disabled cache. Going by this CPU-z screenshot:http://img166.imageshack.us/my.php?i...sempron9zt.jpg
You will note that the x86-64 instruction set is still present. Since this is not my screenshot, I cannot validate it's authenticity. I just purchased today a Sempron 3200+ and as soon as it arrives, I'll go ahead and do some benchmarks, etc.
Also I found this AMD cpu roadmap. I believe this was compiled by numerous sources and outlines some information concerning these new semprons.http://www.c627627.com/AMD/Athlon64/
As far as dual-channel capabilities, if a AMD64 4000+ equiped R4000/zv6000 can do it, the lesser winchesters should also be able to as well. In fact, that is why I became interested in this topic. Having just bought a R4000 with 256MB of ram, I'm in the market for memory.
In this thread, someone has gotten DDR400(PC3200) and has seen improved ram test scores:http://www.notebookforums.com/showthread.php?t=89307
I'm considering upgrading to two 512MB sticks of DDR400 as soon as my R4000 arrives. If Dual channel is supported, that hopefully should make my system fly.
Hope this helps clarifies some things.