XP Home vs Pro for multiple cores

[Patosan]

I read somewhere that Pro supported multiple cores while Home doesn't, not quite sure what they meant by support, I know that Home does work on dual core processor pc. Then I heard that both Home and Pro support hyperthreading. So I'm a bit confused about this. Also I believe that even if the os designed to optimize the workload with multiple cores, it's meaningless if the programs used don't.

Can someone enlighten me in this area ?

[Glenn9999]

If I understand it all properly, Pro was only meant to work with multiple PROCESSORS (as in X processor dies mounted onto the motherboard). The dual-core processor is just that: one processor. There's really a difference, and this is what is different about the licensing options. For the time, there wasn't multi-core dies and most people didn't work with multiple processor die systems, so the differentiation made sense.

Also, the multiple processors (either through one die or multiple dies) do help in most applications in terms of load - the OS can schedule them dynamically among the processors and increase the ability of the system to respond to input. There is a performance benefit to multi-threading something in a multi-processor environment, though most applications will be multi-threaded anyway. The problem in most modern OSes (XP SP3 included) is that a lot of program vendors will try to tie work to specific processors, which eliminates most of what the OS can do to manage the processors.

[Patosan]

Thanks for the reply Glenn9999,

After getting out and asking a few vendors I found that as you say, Pro supports 2 processors which Home doesn't ... though majority of people, incl me, won't utilize that feature. Multi core processors are considered a single processor by XP so both Home and Pro treat them the same. Hyperthreading is same in both Home & Pro.

So now I doubt that Pro is for me ... just wondering if it would assist in my various slipping trials, as thus far my Japanese Home OEM ver has given me months of headache and disappointment ... but that's another question.