Intel Clarkdale Core i5 661 32nm CPU Review

Pricing

The addition of an integrated GPU to the mix has made comparing CPU prices a bit awkward. First, let’s take a look at all the CPUs we’ll be looking at in this review:

As  you can see, I included everything that can be had for between $100-200 today. About the only CPU missing here is the $95 Pentium E6500 – which is just a Core 2 Duo E7500 with half its cache disabled, so you can roughly draw your on conclusions how it would fit in. I suppose I could have included the Phenom II X4 810, but it would be foolish to buy that instead of a Phenom II X4 925 for the same price.

Anyway, the Core i5 661 (and 660, which we’re told is the same price) is available in 1000 unit purchases for about $200 USD. This puts it precariously close to the Core i5 750, which has four real cores. It also directly competes with the X4 965 – AMD’s current top processor – which of course does not include a GPU.

Once you look at the actual cost of an entire system though, things look a bit different. I priced out the current cost of the following components, keeping in mind that the goal of this build is for computing power and multimedia capabilities, not gaming:

• Memory – 4GB OCZ Gold DDR3 1333 ($73)
• Hard Drive – Seagate 7200.11 1TB ($120)
• Optical Drive: LG Blu-Ray Reader/DVD Burner Combo ($120)
• Motherboard for Core i5 660/Core i3: Intel DH55TC ($100)
• Motherboard for Core i5 750: Foxconn P55MX ($85)
• Motherboard for AMD: Asus M4A785T-M ($85)
• Video Card (for the i5 750): ATI Radeon HD3450 (roughly equivalent to the 4200 found on the 785G motherboard: ($40)

Having to buy both a motherboard and graphics card shot the i5 750’s price up quite a bit. But it’s still quite reasonable, and could be made even more so by buying an even cheaper graphics card.

Intel tells us that the H55 board they sent is estimated to retail for about $100 USD in stores. This is worrying, since it is very much an entry-level motherboard with fewer SATA ports and USB ports. The fact that there is not even a Northbridge or GPU on there makes it seem even more expensive. Only time will tell how much 3rd party H55 and H57 boards will sell for. Probably in the $80-100 range.

Overall, the total price of an i5 660 is about $50 more than AMD’s “Core 2 Killer”, which also has four real cores to content with. The i3 540 matches up with the triple-core Phenom II, but we don’t have one of those yet, so we’re not sure how it will stack up.

So which of these systems is the one to buy after today? Let’s find out!

The Test

With Lynnfield, we completely overhauled our test bench, focusing as much as possible on real-world application performance. With this review we have tweaked things a bit more, updated some software, and added some new tests. We’re still using Windows 7 x64 Professional, but this time our AMD platform has been switched from a DDR2 790GX chipset to a DDR3 785G chipset.

Here’s a list of our test setup:

The Corsair ram used in the here is actually a retail kit I purchased at a store. The part number is TW3X4G16009D, and it is officially supposed to run at DDR3-1600 @ 9-9-9-24 at 1.9v. I had absolutely no problems running it at 7-7-7-20 at Nehalem’s stock DDR3 voltage of 1.5v. Expect a review of these bad boys soon (along with the OCZ Blade low-voltage DDR2 series, which are just about as impressive).

SiSoft Sandra 2010

As always, we start out with a look at theoretical performance with SiSoft Sandra. Yeah, I said we would mostly stick to real-world benchmarks, but this program has its use, and remains our one fully synthetic benchmark. It’s interesting to see where performance gains are found, exactly how each feature affects performance, and so on.

The latest version is handy in that it aggregates the scores, easily giving us overall benchmarks to compare.

The first test is the CPU Arithmetic benchmark, which combines both the classic Dhrystone and Whetstone benchmark into one score. We used to separate these two scores, and I may actually go back to that, because it’s interesting to see where each CPU excels in terms of integer and floating-point performance. As it is now, the chart almost directly corresponds to our price chart, with the exception of the quad core Athlon II standing out against the other $100 chips.

The Multimedia benchmark is more reality-based, in that it actually uses the CPU to produce a fractal image (640×480, with 255 iterations for each data pixel, in 32 different colours). This one is very sensitive to new revisions, as versions based on new instruction sets are always being released. This chart is pretty embarrassing for Intel, as they are outclassed by just about everything from AMD.

So far the Core i5 is not much faster than a Core 2 Quad, which isn’t as bad as it sounds, considering it only has two cores. Still, it’s not blowing us away in these synthetic tests.

Cryptography

This relatively new module measures each processor’s performance in cryptography, specifically their performance in encryption, decryption, and hashing tasks. AMD processors typically do very well in this test. This may change though, considering SiSoft Sandra supports Intel’s new AES instruction set:

As you can see, using Intel’s AES instruction set – currently only supported by Clarkdale – provides a huge increase in performance (remember, this CPU only has 2 cores!). This chart doesn’t even tell the whole story, as it combines both AES and Hashing scores. Still, this is just a synthetic test, and until actual real programs start using the instruction set, it’s not quite as meaningful as it looks here.