A question I've had burning in my mind since Intel macs were launched, and sorry if its covered somewhere else, I can't see where, and I cannot find a comment on the apple web site. Is the intel inside the intel macs 64bit?

The Core-Duo is 32 bit only, possible 64 bit release by intel later this year, perhaps to coninside with the powermac release

all duel core processors from intell are 64bit ready. So the answer is yes !

Hmm. Conflicting answers (maybe because the core processors are duelling).

So which is it?

The Core Duos are 32-bit, so in a way the new iMac is a step backwards. But expect 64-bit chips in Macintels before long.

I could be wrong - quite happy to be wrong means I have learnt something today.

However according to this site MAC INEL 64?

The core duo is not 64 Bit - intel have not released any moblie 64 bit process todate, and as the core duo is the latest on the centrino - laptop process it is currently only 32 bit

The chip is a 64 bit chip supporting all the loverly feature that a 64bit chip does.

HOWEVER


The 64 bit part of the chip is disabled. Dont know why but it is. So it is only running as a 32bit machine.

The way I see it is this. Its already way faster than a G5, It has more hyperthreading functions than the fossil altivec. Not to mention some loverly other features. Oh yes its cooler.

The power books were still running a 32bit G4 chip anyway before hand. So really no change there.
The new intel iMacs are way faster than the slow G5 versions a few months ago. Raise your hand if you need more than 4gb of ram in your imac anyway! So it comes down to this.

Slow 64bit chip VS. Fast 32bit chip.

We already know what has won, so quit your complaining

according to more research done on this subject, the 64 Bit function is disabled because intel have not been able to make a stable mobile 64 bit chip. So inessence yes it is 64 bit but its disabled - so no its only 32bit

I thought I knew the answer to this question, but decided to do some checking before answering.

It turns out that current Core Duo and Core Solo processors are 32-bit. I couldn't find confirmation of this on either Apple or Intel's web sites, but found confirmation of this fact in the following Wikipedia article: http://en.wikipedia.org/wiki/Intel_Core.

32-bit vs 64-bit isn't really about speed directly. As I understand it, and I don't profess to have real knowlede in this area, the main benefit of 64-bit is that it can directly address more memory. When a processor can directly access more physical RAM, this in turn makes it faster when dealing with large data sets.

Intel also have a technology for some of their 32-bit processors called EM64T, which allows them to do 64-bit memory addressing. That is (from my understanding), they are still 32-bit processors, but support 64-bit general purpose registers, 64-bit integer arithmetic and logical operations, and 64-bit virtual addresses. However, the current Core Duo and Core Solo processors do not support EM64T according to the Wikipedia article, but the next version (code named Merom) will.

What I found particularly interesting though is that the Core platform is a platform of mobile processors. That is, the processors are intended for notebooks, despite the fact Apple is using them in the new iMac. This suggests that the Core Duo processor won't make it into whatever replaces the PowerMac. Instead it is more likely that a new desktop processor, using similar technologies, will be used.

Firstly:
Most of the speculation surrounding the 64-bitness of the Yonah processor is kind of irrelevant. The Yonah only supports 32-bit instructions. There may be a 64-bit chip in there somewhere (this is the debate) but it only supports 32-bit instructions, so it really doesn't matter.
My understanding is the Yonah might be a 64-bit chip but it DOES NOT support 64-bit instructions.

Secondly:
Intel's new architecture is due Q3 this year. Replacing the Yonah will be Conroe and Merom. Both are based on the flashy new Intel architecture which will deliver 64-bit and significantly reduced power usage. In reality - this is the chip Apple probably targetted to use from the beginning, but decided to begin the transition early with a less capable chip (Yonah).