One advantage to going 64bit is that you can address a huge amount of ram beyond the 32bit limitation of 4gb.. And the lockup problem, I listen to Leo Laporte often, I've heard more than just a few callers that had problems when their Windows machine comes out of sleep mode or whatever the power save options are.. I've heard of lost files, permanent lockups, etc.. that's what makes me despise Microsoft, the ongoing things that never get attended to..
I tried XP64... it seemed OK and fast on certain things... but my audio card is older and I couldn't get my printer to work with 64-bit driver. I guess that's a fairly common problem when you try to use a new OS on older hardware. If you bought new peripherals as well, they'll probably just fine with any 64-bit OS, but I'm not sure MSFT didn't sort of let XP64 "slide" and not make it as good as they could have... considering they were working on 64-bit Vista, then W7. ?? I ran my trading rig for a while (multi-tasking, minus the TV tuner) on XP64 and it seemed the same as on XP 32-bit. In spite of 64-bit "being able to address more RAM", it did not... used about the same as 32-bit. Bottom line (for me)... I'm sticking with XP 32-bit on my trading rig at least until 2014, when support for XP is currently scheduled to end.
"use more ram" means you can install more on the motherboard. If your software won't use it, it won't make any difference.. Probably Photoshop would be the main software that I can think of that would use the extra ram but some of these backtesting softwares might be able to use it, not sure about that at all... I'm googling and not seeing anything definitive about "modular"... that's the main thing that I want really, along with airtight security...
This is an excellent point, and one I had not considered. A 64-bit OS will address more memory than 4GB, but 32-bit apps will not. The 32-bit address space is only 4GB. Maybe there are some fancy tricks (e.g. far pointers) I don't know about that allow a bigger address space. So it sounds like having more than 4GB memory only allows us to load up more programs. That's a pretty minor benefit. It sounds like I'll be staying with a 32-bit OS (probably WinXP) for now.
You will still have a significant advantage even for 32 bit software as any given program can use up to full 4Gb. That 4Gb of memory is not being eaten up by the operating system, buffers etc and other programs. More memory will often help system performance overall even if an individual program doesn't need it all. Because more memory is available for buffers - especially file system buffers. Providing of course you put 8 Gb in your machine.
If I was getting a new machine I'd get 64 bit Win7 and about 8 Gigs of ram just to be on the safe side... ram is usually the least expensive way to get more performance... These mobos with huge, I mean huge ram capability may make ramdisks way more attractive.. some software that is slow because it accesses the disk a lot could load the data up in a ramdisk..
I listen to Leo a lot. Great show. I have had problems with power save and sleep mode with all versions of Windows that I have used so when I get a new machine which is rare the first thing I do is turn off the power save, sleep mode options.