64 bit question

[southpaw13]

Might be a stupid question....
I see mame has a 64 bit version, If I buy a 64 bit processor, do I also need to run a 64 bit version of Windows?   I am assumming that I do, but just thought I would ask...

Thanks....

[crummy]

You can run 32bit programs (and 32 bit Windows) on any 64bit processor you can easily buy. At full speed, too (which wasn't always the case).

If you want to run 64bit MAME, you need to be running 64bit Windows, on a 64bit processor.

[northerngames]

athlon 64's work fine with regular 32-bit windows and apps.

they also are a p4 killer.

[u_rebelscum]

You can run a 32 bit and/or 64 OS on a 64 bit CPU.
You can run 32 bit and/or 64 programs on a 64 bit OS.
You can run 32 bit programs on 32 bit OSs.
You cannot run 64 bit programs on 32 bit OSs.**
All current CPUs by intel and amd are 64 bit.*


*Just to be clear: P4s, athlons, celerons, semprons & xeons started as 32 bit CPUs, but current models are now 64 bit.  And while the core2 desktop was always 64 bit, the core2 mobile started as 32 bit, but currently is 64 bit.  PIII, PM, core (1) duo/solo, and older were only 32 bit (until you get back to the 16 bit 286 & 386sx).
So if you're looking at old computers with CPUs with those mixed 32/64 brand names, be sure to check that the CPU version in that computer is 64 bit if you are looking for 64 bit CPU.  IOW, the general brand name is not enough in many cases.

**And just to be clear 2: you technically can run 64 bit programs on 32 bit OSs under very special cases.  One case being using 32 bit mame to run a 64 bit arcade game on an emulated 64 bit CPU.  However in any case, it's VERY slow, you need an emulator pretending to be the 64 bit CPU and/or 64 bit OS, and not usable.  So even though it's possible to "run", it's not possible to use, thus the simplification that you can't run 64 bit programs in 32 bit OSs.

Sorry for my at the end.

[southpaw13]

Great stuff----Thanks everyone!!!!

[FooMonk]

It's my understanding that if you run a 32 bit OS, it's still only got a 32 bit address space, so you'll be limited to 4GB of RAM, even though your hardware can handle more.

[southpaw13]

So lets say you were going to buy a 64 bit OS.  What is the best way to go for Mame?  XP or Vista?

[u_rebelscum]

It's my understanding that if you run a 32 bit OS, it's still only got a 32 bit address space, so you'll be limited to 4GB of RAM, even though your hardware can handle more.

Yup.  All the limits of the 32 bit OS, with almost no benefits due to the CPU being 64 bit.  You do get one (can't find the link on what, a post by R. Belmont IIRC) due to 64 bit, and you get all the other faster CPU stuff, like higher IPS, SSE, ect that modern CPUs have over older 32 bit CPUs.  (I'm talking about PCs, here.)

So lets say you were going to buy a 64 bit OS.  What is the best way to go for Mame?  XP or Vista?

Yes.     Either those or a 64 linux + sdlmame(64).

Just make sure your hardware has drivers for whichever OS you choose.  From what I hear, Vista64 is better in general than XP64.  However, as a generalization it's not always so; AFAIK, there are some stuff with XP64 drivers and not Vista64 (probably stuff not on the market any more).  And with Vista the new OS, XP64 won't get very many new drivers while Vista64 will/should.