Intel Core i5-661 & Core i3-530 CPU Review

Testing Recap

We could only get our hands on the Core i5-661 and Core i3-530 models of the new range of Clarkdale processors for this article (see The New Range Explained for more details on these). This meant that we needed to compare these new CPUs to the rivals already on the market: Intel's Core i5-750 and AMD's Phenom II X4 965 Black Edition cost roughly the same as the Core i5-661, while Intel's Core 2 Duo E8400 and AMD's Athlon II X4 630 cost roughly the same as the new Core i3-530.

We wanted to see whether Intel's Core 2 Quad Q6600 could still cut it against these new processors too, so re-tested that in our new Windows 7 test rigs. You can read the Testing and Overclocking page to see more details on how we tested all the CPUs.

Performance Analysis

If Intel is seeking to name its CPUs in order of application performance, then our results show it’s got it just about right. At just a touch under 3GHz, the new i3-530 is the slowest of the Nehalem-derived CPUs, but it's a lot quicker than a comparably clocked Core 2 CPU such as the Core 2 Duo E8400 - 48 per cent faster in video encoding, for instance. Despite the fact it's only a dual-core chip, it manages to outpace the legendary Core 2 Quad Q6600 at stock speeds in this same test. In fact, you'd need need to overclock the 8400 to over 4GHz to get it to the same pace as the i3-530 when it comes to video. In the multi-tasking test, the i3-530 has less of an advantage, but overall it's still 22 per cent quicker than the stock-clocked E8400, showing a considerable clock-for-clock improvement.

Higher up the new range, the picture isn't quite as rosy. The older, Lynnfield-based Core i5-750 was a touch faster than the new Clarkdale Core i5-661 in our Media Benchmarks. The Core i5-750 was much faster than the Core i5-661 in Cinebench, as four slower physical cores are better than two faster Hyper-Threaded ones, and the same was true of wPrime. As expected, the dual-core Clarkdale CPUs consumed less power than the quad-core Lynnfield, with the test system with an Core i5-661 installed sucking 115W from the wall compared to the 160W consumed with the Core i5-750.

The situation changed when we fired up our two game tests – as usual, we saw evidence that a fast dual-core will outpace a slower quad-core CPU. With both systems running the same graphics card, a Radeon HD5870, Crysis ran at a minimum of 25fps on the new 3.33GHz Core i5-661 while the 2.66GHz Core i5-750 could only muster 20fps. X3: Terran Conflict is a bit more quad-core friendly, as the Core i5-750 could manage a minimum of 43fps and the Core i3-530 38fps.

So, in terms of competition against its own, older CPUs, we can say this is mission accomplished for Intel - the Nehalem architecture scales downwards well, and Core 2 can now be spoken of in the past tense - but where does all this leave AMD? As we wrote earlier in the article, its own CPU/GPU chips are a long way off, so it's stuck with the Phenom II for the time being. That said, it's not a total disaster - the 2.93GHz i3-530 is kept in its place by the Phenom II 965 BE. Intel's cheap new CPU is around 14 per cent quicker in our 2D benchmarks than the 2.8GHz Athlon II X4 630, despite having only a four per cent advantage in clockspeed, showing Intel's design is more efficient.

Higher up the new Intel range, and the likely comparably priced Core i5-661 is only a mere 43 points - that's three per cent - faster than the Phenom II X4 965 Black Edition overall in our Media Benchmarks. Looking at the minimum frame rates, the Core i5-661 was 2fps faster than the 965 BE in Crysis and 3fps faster in X3, while it was twice the speed of the Q6600 in both games.

Overclocking does wonders for the i3-530 - at 3.5GHz it's faster, overall, than a 3.7GHz Core 2 Quad Q6600, and it's likely this chip will cost around £80 to £90. It's also only eight per cent slower than the Athlon II X4 965 BE at 4GHz, which is a poor show for AMD. Still, when all the CPUs were overclocked, there was no competition in terms of raw pace for the Lynnfield Core i5-750 running at 4.1GHz.

It's interesting to see that where overclocking once managed to lift the Q6600 to greatness, it's now a CPU showing its age - the i5-661, i5-75- and 965 BE have average framerates seven to 12 FPS higher in Crysis than it. At 3.5GHz, the overclocked i3-530 is pretty nippy too, its average of 49fps faster than the Q6600 by a touch.

Conclusion

The Clarkdale Core i5 and Core i3 CPUs are worthy successors to the Core 2 Quad and Core 2 Duo and if you're looking to buy a new Intel system, there's really no way you ought to be looking at Core 2 chips any more, especially as the i3-530 expected to come in at under £100, while offering Q6600 levels of performance. In fact, paired with a good, cheap overclocking motherboard, we can see the i3-530 being a great budget buy. At 3.5GHz, it's quick and of course, it has excellent power consumption figures. It puts AMD's cheap CPUs under serious pressure, and we wouldn't be surprised if AMD needed to resort to a price cut to make its CPUs as attractive as they were prior to Clarkdale's arrival.

The faster Clarkdale CPUs face more competition from AMD - while i5-661 kept the AMD Phenom II 965 Black Edition at bay in most tests, the 965 BE shone in heavily multi-threaded applications - but it's Intel's own Lynnfield, particularly the i5-750, that really does the damage. Particularly when overclocked, the i5-750 is a monster in terms of performance at this budget. Despite, in all likelihood, being almost identically priced, in 2D benchmarks, a 4.15GHz Core i5-750 is around 30 per cent faster than a 4GHz i5-661 - a number which we think will make it very easy to make your buying decision.

Intel Core i5-661

• Performance
• x
• x
• x
• x
• x
• x
• x
• -
• -
• -
• 7/10

• Value
• x
• x
• x
• x
• x
• x
• x
• -
• -
• -
• 7/10

• Overall
• x
• x
• x
• x
• x
• x
• x
• -
• -
• -
• 7/10

Intel Core i3-530

• Performance
• x
• x
• x
• x
• x
• x
• -
• -
• -
• -
• 6/10

• Value
• x
• x
• x
• x
• x
• x
• x
• x
• -
• -
• 8/10

• Overall
• x
• x
• x
• x
• x
• x
• x
• x
• -
• -
• 8/10

Score Guide