First up, is the Core 2 Duo E6400 versus the Core Duo T2600. These both have a shared 2MB Level 2 cache and operate at very close clock speeds (2.13GHz and 2.16GHz). The only major difference is that the T2600 runs at DDR2 667 instead of 800MHz.
This test really illustrates how much improvement has been made to the Core design, before any extra cache is even added. In Photoshop Elements, a significant 62 seconds, or a 12 per cent improvement is seen. Similar improvements were seen in other areas, including a 24 per cent improvement when compressing a large file and a huge 21 per cent for video encoding. All in all, it averaged out to a 12 per cent improvement in performance.
In gaming, the situation wasn't quite the same, with the Core Duo actually performing better than the E6400 in Call of Duty 2. This victory was short lived though, with every other game running faster on the E6400. However, when run at the higher 1,600 x 1,200 setting it was interesting to note that graphics card limitation caused no discernable difference in performance.
A better comparison for desktop parts, would be against its previous NetBurst processors. This is where the biggest difference is noticeable as they are the slowest of every processor on test. Even the budget E6400 beat the previous ~£700 955 Extreme Edition in everything but Call of Duty 2. If you want more detail than this, go and see the results for yourself – but everything simply wipes the floor with Netburst.
The next question, is how does Conroe compare to the Athlon 64 architecture? For this, I used the overclocked Athlon FX-62 at 2.92GHz to match (almost) the frequency of the X6800. In fact, the FX-62 gets an unfair advantage as being overclocked it has slightly faster memory frequency. It is doubly unfair, as an Athlon rated above 2.8GHz is not yet available.
Luckily for AMD, the difference wasn't quite as big as the hype led us to believe. On average the X6800 is 18 per cent faster. Don't get me wrong – this is still a fair chunk. An area where Intel had a clear lead was with Audio encoding where the X6800 was as much as 40 per cent speedier. Video encoding was also 25 per cent faster on the Conroe based chip – that's 239 seconds difference. Considering that was only on a 15 minute clip, there are some significant savings in time to be made with larger files. Thinking even further a field, if you are in the business of render-farms, this could really make a difference to productivity.
As with everything, it's not just about the technology, it's the final product. The Athlon 64 architecture might not be as far behind as we thought – clock for clock. However, pushing an Athlon 64 beyond 3GHz is currently a difficult task and even with a future die shrink to 65nm I don't see it scaling as well as Core 2 Duo. If you take a close look at our benchmark results, you'll see that the 2.66GHz E6600 is faster than an FX-62 in almost all cases and costs around a third of the price. Things don't look good for AMD at all if its flagship product can't stand up to a mid-range part.
Intel has already demonstrated quad-core technology, and has the ability to push clock speeds to 3.46GHz and above - even with the current steppings as I discovered myself. So the future is looking very strong for Intel.
Conroe/Core 2 Duo is the single most significant launch in the desktop area in years. It is a truly excellent product offering great value for money, cool running and low noise. Judging by the pre-purchase pricing on Overclockers, the E6600 is looking to be the choice chip right now and should be high on your wish list.