How many procs can XP Pro or Vista use at once?

[dnuggett]

I am thiking of going to a dual core dual proc Opteron setup in the near future. I know XP Pro is multi aware... but will be it aware of 4 cores and utilize them appropriately? Also what's the word of Vista's awareness on dual procs/cores?

 

[ValuedCustomer]

That's a very good question. - my knee-jerk is to say that XP Pro won't use both but only the 2 cores from #1 but I can't find any confirmation/denial on M$'s site.

When running a dual-core w/ XP Pro aren't there 2 windows for CPU usage in task manager? If you have 2 dual-cores this would mean there'd be 4 windows?

/scratches head

 

[Smilin]

XP supports dual CPUs.

This is two single CPUs or a single dual core.

Two dual cores would be 4 cpus. You would want to go to Server 2003 for that.

 

[Smilin]

Also the only way you'll see 4 processor graphs in task manager under XP is if you use dual cpus (or a single dual core) that is also hyperthreading capable.

 

[mechBgon]

Reality check:

WinXP Pro, 2 x dual-core x HT = 8 CPU graphs. Unless they faked it...

 

[ValuedCustomer]

It took me a sec (I shoulda just rtfa) to realize what the 8 windows were for. - That's weird.. pretty cool but weird. 😛

 

[bearxor]

Microsoft has said that they license their OS by socket, not by cores. So if, in theory, you had a quad-core dual-proc P4 machine with hyper threading, XP should be able to recognize up to 16 threads.

So, XP Pro and 2000 Pro recognize two processors. Vista will likely have a Home/Pro edition, which will support 1 or 2 sockets.

Contrary to public opinion, you do not need XP Pro to support a HT processor, or a PentiumD.

 

[Smilin]

I stand corrected

 

[ProviaFan]

Originally posted by: bearxor
Microsoft has said that they license their OS by socket, not by cores. So if, in theory, you had a quad-core dual-proc P4 machine with hyper threading, XP should be able to recognize up to 16 threads.

So, XP Pro and 2000 Pro recognize two processors. Vista will likely have a Home/Pro edition, which will support 1 or 2 sockets.

Contrary to public opinion, you do not need XP Pro to support a HT processor, or a PentiumD.

Additional clarification: 2000 Pro doesn't understand the "per socket" licensing, so while a dual core or HT processor (singular) will work fine, anything that puts the number of virtual or real cores over 2 will not be fully utilized. Of course - conveniently for MS's pocketbook - XP does not have this limitation, as correctly stated above.