I purchased Windows XP Pro SP2 (32 bit) last year but I didn't use it. Lately, I've been reading Intel Quad Core 2 Q6600 reviews and about its recent price drop. Compared to Vista, what would the performance be if I used XP Pro instead? I've read a number of Q6600 reviews and the testers all seem to use XP Pro. Vista has a new feature for quad cores called "load balancing." How much of a difference would it make if I used XP which doesn't have this feature?

I will be running 2 CPU intensive business apps and a special permanent memory resident disk program. If I bought the Q6600, using XP Pro, is it possible to manually assign the last 3 cores to these tasks? I would leave the first core for regular system usage and other apps. Would this setup work in XP and would there be any performance difference compared to Vista? I do not want to buy a whole new set of software again.

Thanks.

Correctly me if I'm wrong,

WinXP uses (and requires) less resources than Vista does.
Hence allowing you to use your hardware more efficiently.

Unless you really need/want the new software, such as media center or DirectX10 etc, in Vista there is no real reason to use Vista especially when it comes to business usage.

Last but not least, WinXP allows you to set the affinity for each process to one or more cores.

So in short to answer your questions in order I would say:
1) The difference is most probably none existent if at all noticeable.
2) Yes you can assign to the core(s) of your choice.
3) Yes there would be an advantage in performance using WinXP over Vista.

Anosh,
Thank you for your response. In XP Pro SP2, where and how exactly do I assign a business application to a specific Q6600 core?

Open Task Manager (with Ctrl-Alt-Del).
Right click on your software (assuming you're in the application tab) and choose Go To Process.
Right click on the process that has been marked and choose Set Affinity.

Unfortunately I do not know of any (built-in) means to make WinXP remember the Affinity you set which means it would have to be done every time the software is started.

But I do know of this program that does set the Affinity of your choice through a shortcut:
http://www.ice-graphics.com/ICEAffinity/IndexE.html

Also there is another option through which your software can be modified to permanently have a certain Affinity but in your case I'd rather recommend setting it through a shortcut.

To my knowledge Vista doesn't have any feature allowing for permanent Affinity either but on this point don't take my word for it.

I would disagree with you. Vista is, admittedly, more aggressive on the resources than XP. More aggressive is the preferred term, in a sense that, for example, it uses memory, if available, to run [I forget what that feature is called any more; effectively preloading data].

Vista, technologically, is way superior. I do prefer it, personally, from the aesthetic point of view as well, but tastes differ. But the point where I think you are wrong the most, is that it makes sense the most for business usage, as in spreadsheets, typing, etc. The problem with Vista is [certain] hardware and software compatibility, and MS Office works just dandy in it. Btw, the new office is head and shoulders above anything previously released. With gaming uses, it's not clear cut. There are certain problems with Gfx and Sound drivers, I think, lingering to this point, so certain games are not as Vista-friendly as you'd like. Plus, certain copy protection schemes in some games do not work well on Vista, as users reported having to run noCD patches to make the game work (incredibly ironic). So, if you game a lot, Vista may not be the perfect choice still, although it is my understanding that the issues are being worked out as time goes on. But for business usage - unless by that you mean usage in a big corporation with a lot of proprietary [and, most often, somewhat pourly coded] software with unknown compatibility that you rely on for business continuity - is where Vista makes all the sense in the world.

Also, Cypherdude, it is my understanding from what I've read that Vista's scheduler is Far superior to XP's, so the system does a pretty good job of load-balancing without setting the affinity manually. And in XP, setting the affinity often does Not result in increased performance if the application isn't coded to take advantage of multiple cores, simply more even load spread.

I have researched it alot, just don't bother with Vista at all until it matures. Too many problems with it.

anosh,
The ICE Affinity program you gave doesn't seem to be written for 4 cores, only 2. Look at the options for setting Affinity. I did a search for the keyword "Affinity" and this program does seem to work for 4 cores: http://www.beyondlogic.org/solutio [...] ssutil.htm

Thanks for your help though.

russki,
actually, I am more interested in load spread than anything else. If I am going to run 3 CPU intensive programs, none of which are written to run on multiple cores, I would like for each of them to run on a separate core. Hopefully, they can run on a specific core without crashing. I think this can be done. I'll only know for sure when I actually install everything and run them.

Cypher - While it doesn't have sophisticated load balancing algorhythms like an enterprise class server does/would/should, Vista is intelligent enough to assign different programs to run on different cores. Memory permitting, you should see little performance hit while multitasking. I can compile a video and play a game on my dual core box with no troubles, for example, and not have to instruct the OS at all. Both cores of my processor show plenty of load. You'll still see some slowing due to HDD I/O, but the memory/cpu/gpu will handle their parts just fine.

No, it isn't perfect, but you won't be beating the tar out of one core with all your programs while the other three do nothing. It just can't multithread applications across multiple cores unless the apps were specifically written to do just that. But know that that is upon the application developer, not an OS problem.

As I mentioned in my original post, last year I purchased XP Pro SP2 but I never used it. I wanted to know what kind of performance hit a Q6600 system would take running XP instead of Vista and if I could assign the 4 cores to specific apps. I don't want to spend another $500 in software. If possible, I'd rather use what I have.

Also, I agree with Falken699 regarding maturity of drivers. I think Vista was released too early because some drivers are either nonexistent or buggy. I'm not even sure my business software will work stably in Vista. Thanks everyone for your input.

Software compatibility would be the biggest concern. If it is expensive and hasn't been tested, maybe it's not worth being the guinea pig.

As far as what Falken said - I don't know what he was researching. I've used Vista and it is at least as stable as XP in business-oriented use. As far as your point re: drivers, well, MS would tell you it's the IHVs. They seem to be right, too.

Again, load balancing (even if that's all you are after) is better in Vista, at least that's my understanding.

From what I understand, Vista is better suited for running multi-core CPU's than XP is.

Vista is **excellent** for severely throttling network performance when playing mp3's. Four cores should really shine in that situation.

russki,
Because I already paid for XP Pro SP2, I guess I'll find out. As I mentioned, there's a program which allows you to permanently assign a CPU core for a particular program. I think that's pretty cool BTW.