TBH, I find your question a bit meaningless. Why omit the OS? What I am interested in is how fast the totality runs - OS and "applications", as I never run the applications without the OS; obviously I'm particularly interested in the applications that I run. For me the combination of a 64-bit OS and the applications I run is faster than a 32-bit OS with similar (or even the same) applications. Why that should be is irrelevant, and it matters not to me if others think differently.

You'll need a pretty hefty solution to max out your memory with VS.

You think I only run VS and don't have other applications open at the same time? Again, to consider only single applications is meaningless. You have to look at the totality. If I'm running Solaris in VirtualBox, with 2GB of RAM, at the same time as VS the totality becomes quite important - especially if the OS only lets me use 3GB of my 4GB RAM.

Placebo effect, we've found no such thing in our company.

And your computers have exactly the same spec as mine? I doubt it.

At this point I have 3103MB available RAM, out of a total of 4095MB. You are seriously telling me that I would have more available with 32-bit Windows 7?

You don't have to sell me on the benefit of more memory, my computers have 8 GB. But the scope of the question was a single application for an everyday user, not an arbitrarily complex set of interacting ones for a developer.

John.

True. I have failed by attempting to give a meaningful answer to a meaningless question.

Really, I don't give a damn whether people choose 32-bit Windows or 64-bit.

fair point about the OS, but to say my question is meaningless is daft. If the only benefit of 64bit Windows is Windows itself is it really worth it?

Photoshop/Lightroom, used by a lot of photographers, will give a 8% to 12% performance gain (excluding the ability to handle larger files/memory which can really make 64bit fly compared to 32bit)

A lot of applications aren't available in 64 bit - so comparing hard, but lets be honest most applications wouldn't be noticeably a slower on a slower CPU so any gains on them would be negligable in use

I'd put 64 bit on - it means if 64 bit versions become available that give you better performance, you can use them

If it doesn't cost any more and 64-bit Windows runs faster than 32-bit, is it worth it? Tricky question - I'll have to think that one over.

Remember - if you later add more memory and want to go to 64 bit from 32 bit is is a full clean install so you will lose everything and have to reinstall all your other programs etc.
The other thing, which I am sure has been mentioned, is that total memory includes the memory on the graphics card so a modern card with 1GB ram will reduce the effective available memory in windows 32 bit down to about 2.5GB