I have a Core 2 Duoo E6600. As far as I know, this is x86 and I should install an x86 OS.

However Everest reports that this processor supports 64-bit x86 extensions.

What does this mean? Can I install Vista x64 version?

Thanks

Yes. x86 is a rather general term that has come to mean Windows-compatible and compiled programs and such. x64 means 64-bit, these days. Kinda confusing. Your E6600 will do it fine.

x86 means any CPU using the x86 architecture such as the 386, 486, pentium, pentium2,3,4 etc.... which are all 586s. The AMD k7, XP, etc... which are all based on x86 architecture. Any OS such as windows designed for an x86 CPU requires an Intel or AMD CPU. Linux distributions have to be marked as x86 compatible to run on AMD or Intel CPUs.

Yes the new Intel Core 2 Duos are 64bit compatible and will run on Vista 64bit.

I think it should be noted that there are indeed other manufacturers of x86 CPU's out there. VIA makes some nice ultra-low-power chips, and I'm sure there's a couple other small producers.

To add to what these other folks are saying, the term "x86" was an abbreviation of the original part numbers used for Intel processors. The first one of the current generation was 8086, followed by 80286 (80186 never really made it into PC's), 80386, 80486, etc. At one point they were all grouped under the "x86" umbrella, which was mostly a statement of binary compatibility.

x being the variable.

Ok, so on this system:

E6600 Core 2 Duo @ 2.4Ghz
2GB Samsung DDR2 SDRAM @ 667Mhz
nVidia GeForce 7950GX2

Should I install Vista Home Premium x86 or x64?

Also can someone help me decipher this PM I got, doesn't make much sense to me:

"There is a glitch in EM64T that Intel has promised is fixed but you will have an additional headache or two .

"EM64T is targeted to 64-bit operating systems. Period. If you’d like to buy a 64-bit Celeron D or Pentium 4 for when Windows 64 and native 64-bit software reach the market, go ahead. But keep in mind that you won’t be able to use EM64T exclusive features unless you run a 64-bit operating system AND 64-bit software.

If you have a 64-bit Celeron D or Pentium 4 and Windows 64, 32-bit software will run just fine, however it will run under compatibility mode, meaning they will “see” the CPU as a regular Intel IA32 engine. If you use “heavy” applications and are thinking of moving to 64-bit computing to have more than 4 GB RAM available, keep in mind that you will need new 64-bit version of your software, or they will still access only 4 GB RAM, thus not solving your problem.

Also keep in mind that the external address bus of EM64T-based CPUs isn’t 64-bit wide, so no Intel CPU using this technology can access 16 EB (exabytes) of RAM (2^64), as you may think. The maximum amount of RAM memory a CPU can access under 64-bit mode depends on its implementation. 64-bit Celeron D, Pentium 4 and Xeon CPUs can access up to 64 GB of RAM while 64-bit Xeon DP can access up to 1 TB of RAM. Once again, keep in mind that under 32-bit mode or 64-bit compatibility mode, the CPU accesses only 4 GB of RAM, even if it is a “64-bit CPU”. http://www.hardwaresecrets.com/printpage/262/3

So yes it will run Vista just fine but if you run a 32 bit' app it will revert to IA32 instructions and run in 32 bit mode. 32 bit is actually faster than 64bit unless you need to address gobs of memory >4gb.

I would avoid Vista for the time being because too many devices lack drivers and there are too many software incompatiblites (200+ major programs at last count). Also EM64T compiles differently as the extensions are not exactly identical to AMD64 which Vista is compiled for.

"There are also temporal ISA incompatibilities. Intel introduced SSE2 instructions to the Pentium 4, and these were later adopted by AMD as part of AMD64. AMD introduced 64-bit extensions and extended register sets to the x86 architecture with AMD64, and these were eventually adopted by Intel. Intel introduced SSE3 instructions with EM64T, which AMD adopted soon thereafter, and Supplemental SSE3 instructions with Core 2 which create binary incompatibilities between Core 2 processors and current generation AMD64 processors. The PGI Unified Binary allows users to leverage these innovations as they occur, but without generating code that is sub-optimal or simply does not work on competing processors." http://www.hpcwire.com/hpc/1096734.html

I retired from here http://www.sandia.gov/about/index.html so I had an opportunity to confront the compiler issues on Thunderbird. You can see the before and after results of fixing the linux 64 bit compiler here. http://www.top500.org/system/ranking/8114"

I'm running XP x86 64 bit on my E6600 just fine with no issues and will soon be loading up Vista in a 64bit flavor.... Go for it if you are comfortable that you can get 64bit versions of all your drivers.

That PM was too long winded to decypher - you'll be fine...

Ok:

a) how will I know if I can get 64 bit drivers?

b) is there any actual advantage to XP or Vista 64 bit over 32 bit?

Check your hardware vendors and see as far as teh drivers go....most vendors have one flavor or another either there are coming.

As far as advantages - meh? Coolness factor?

To question b): This depends on how often you do a fresh install of Windows on your machine. I don't like to have to upgrade my OS just to handle the extra RAM I put in my computer after a year or two of having it. This happened to me when I was running WinME and moved up to 1GB of RAM. Luckily, XP had just come out and it would handle the "extreme" amount of RAM.

You might think 4GB of RAM is plenty today, but in two or three years you'll probably want more. If you put in Vista 64-bit now, the RAM upgrade later is a piece of cake.

Go with Vista x86 as it be less of hassle in the short term. As someone running both versions on test machines driver support is much better on the x86 version. Drivers for older hardware may never show up for either version. I would also strongly recommend duel booting for the first year. In that case installing the 64bit version becomes less of a hassle which is what I've done with my home computer.

What was the point of this guy's spam?

Completely wrong. X86 is just an abbreviation of 8086...286...386etc. Nothing to do with manufacturer ID. 8088 is just another old member of the 8086 family, 8088's are crippled 8086's which had their 16bit external bus removed and an 8 bit bus put in place. This was done purely for economic's to allow cheap 8bit motherboards, and controller chips to be used in early PC's. Intel made the 8088 as well, and it was the 8088 at 4.77mhz that IBM selected for the original IBM PC.

As for the 'Glitch' in EM64T. I believe that the first 64bit Xeons and Prescotts which had EM64T enabled were based on a slightly outdated specification. AMD had added 2 more instructions and those early EM64T chips didnt have them. Microsoft knows this, and doesnt use those instructions in XPPro-64, or Vista-64.

Im almost certain that newer intel chips, (PentiumD, and certainly Core2 Duos) include those extra instructions anyway.