First of all, we would like to underscore that neither the Athlon 64 X2 nor the Pentium D will be available before summer. Although Intel already launched the dual core Pentium Extreme Edition, it will remain a very exclusive product until the 945 platform and the Pentium D are officially released. AMD announced plans to start shipping the X2 to major OEMs in late summer, and does not anticipate wide availability before the end of Q3.
Thanks to generous preview offers, both Intel and AMD made it possible to have a close look at their upcoming technologies weeks ahead of the actual product launches. After a deep look at all the interesting facets of both dual core technologies, the results are rather disappointing - for Intel.
There are some things we feel like commenting on from a performance point of view. If your applications benefit from dual core processors - see our benchmarks - the Athlon 64 X2 is superior to the Pentium D 840 in a vast majority of our benchmarks. In addition, it is not any slower than its single core counterpart Athlon 64 4000+. Please note that we used a processor based on the old Clawhammer core, which explains the performance handicap when compared to the X2. The latest San Diego core will perform exactly as the X2.
When looking at the Intel lineup, the dual core Pentium D stops at 3.2 GHz, with the single core chips going all the way up to 3.8 GHz (Pentium 4 570). As a result, the Intel dual core chips will be somewhat slower under single-threaded environments if you consider replacing your system at an early point.
Let's have a look at the platforms. Each of these upcoming Athlon 64 X2 dual core chips can be deployed in standard Socket 939 motherboards (AGP and PCI Express) as long as the motherboard maker provides an updated BIOS. Needless to say, the X2 is perfectly suitable as an upgrade chip as well. On the Intel side though, a new motherboard based on nForce4 Intel Edition, 955X or 945 (still to come) is imperative due to minor pinout changes Intel went through. It is odd to see that a current, stable, corporate 915P Intel system won't be able to host a dual core Pentium D, while many NVIDIA nForce3 or VIA K8T800 Pro based motherboard can be upgraded in order to provide service for, let's say, at least 12 more months.
The performance drawback on Intel's side is something we would absolutely be willing to live with for the sake of the multi-tasking experience, and we don't really expect the Pentium D to have any trouble being accepted by the market. However, there is something that we can't really tolerate: the Pentium D system manages to burn over 200 watts as soon as it's turned on, even when it isn't doing anything. It even exceeds 310 W when working and 350+ W with the graphics card employed! AMD proves that this is not necessary at all: a range of 125 to 190 Watts is much more acceptable (235 counting the graphics card). And that is without Cool & Quiet even enabled.
Here's the bottom line. If we had to recommend a single core processor, the choice would depend greatly on the type of applications in use. But in the dual core arena, though, there is not much that speaks for Intel: go with the Athlon 64 X2.