Should I have waited for 64-bit?

[jschunkew]

So I just ordered a 2378DXU thinkpad and
agonizing over whether I should have waited
a year for the 64-bit processors. Longhorn
is supposedly going to have a 32-bit flavor and
the DXU is DirectX 9 compliant so maybe it'll
be OK for several years. Dang I havn't received
the thing and it seems to already be outdated!@W

[ZPrime]

intel 64-bit on the desktop is a bit of a way off. plus, intel 64bit is crap compared to amd64. the only way it would be worth waiting for is if IBM made a thinkpad with an amd64mobile on it, and even then only if you like stuff with no battery (think loaded-up G or R series, not a nice T).

You'll be fine with a Pentium-M, trust me.

[K. Eng]

Short answer - No, its not relevant now for most people.

The chief advantages of x86-64 are (1) 64-bit memory addressing to overcome the 4GB memory limit of 32-bit processors (2) Extra General Purpose Registers. I know x86-64 doubles the number of general purpose registers to 16, but I don't know how many additional fp registers there are.

So you will have to ask yourself if you need 4GB+ memory capacity. For most people, the answer is no. Maybe you would need that much memory if you were running some strange scientific simulation or a huge database, but you wouldn't be using a ThinkPad or other notebook for that. 4GB+ memory won't speed up Windows, office tasks, or Doom 3 at all.

Then ask yourself if you will benefit from the extra GPRs. In order to use the extra registers, your software needs to be recompiled with a compiler that will generate code using the extra GPRs. Currently, there is no commercially available version of Windows that fully supports x86-64, although you can find test candidate versions. You are left with Linux or other 'nix type operating systems with x86-64 support.

In the near term (next year or so), there is IMO no benefit to x86-64. It certainly doesn't hurt to have it, and it does provide a measure of future-proofing, but lack of 64-bit won't hinder most people.

I don't expect 64-bit windows to take off until Longhorn, and by then, x86-64 computers should be pretty much universal.

[K. Eng]

Just to clarify - both AMD and Intel use the same x86-64 instructions. AMD calls it AMD64, Intel calls it EM64T. Both companies also support the No-execute bit to help ward off buffer overflow attacks (AMD calls it NX, Intel XD).

AMD's current performance advantage is attributable to the Athlon 64's integrated memory controller and shorter pipelines (and the Prescott Pentium 4's ridiculously long pipeline, inability to scale, and relatively high memory latency compared to A64).

intel 64-bit on the desktop is a bit of a way off. plus, intel 64bit is crap compared to amd64.
...
You'll be fine with a Pentium-M, trust me.