Intel Clarkdale Core i5 661 32nm CPU Review

Integrated Graphics Performance

As I had mentioned earlier, Intel (and hopefully everyone else) knows that if you want to play games at high resolutions, with high image quality, integrated graphics just aren’t going to cut it yet. They specifically name games like World of Warcraft and Sims 3 in their marketing material to back up this point.

Rather than gather a whole slew of games with crappy graphics, we’re going to use our standard game benchmarking suite, and knock down the settings a bit. We’ll be putting the Core i5 661 up against AMD’s latest IGP – The Radeon HD4200 found on the 785G chipset. This can be found on the cheapest of AMD boards (there is even an ASRock DDR2 board out there with 128MB of integrated memory for about $60).

We put it up against the Phenom II X4 965, since it is as close as AMD gets to the price of an i5 661 with an H55 motherboard (if you add CPU + Motherboard, the Phenom comes to about $285 while the i5 661 should come to roughly $300)

Here’s a quick look at the results:

Aside from the ridiculous Unreal Tournament 3 results (throw those out), the Clarkdale IGP is quite evenly matched with the 785G. Of course, this one is running at 900 MHz, while most will run at 733 MHz, so the units sold in stores will actually end up being slightly slower.

We also took a look at Blu-Ray playback – basically this means confirming that hardware acceleration exists. I’m happy to report that the GMA in Core i5 and i3 is supported by the major Blu-Ray playback software (PowerDVD, WinDVD) including VC-1, h.264, and MPEG-2 hardware acceleration.

Of course, if you are using a processor like the Core i5 661, you don’t exactly need hardware acceleration – the CPU would do a fine job of it. In fact, I disabled hardware acceleration, and found CPU usage to be not much higher. If you are using an old dual core or an entry-level CPU, then it would make a world of difference. With today’s $200 CPU’s though, I don’t see much benefit. We’ll have to wait and see how the Core i3 performs with and without hardware acceleration.

Here are the results of some 1080p VC-1 playback at 1440×900 (our test bench monitor is a bit small for 1080p playback).

Out of curiosity, I popped in the slowest AM3 CPU I could find (an Athlon II X2 250) and the CPU usage increased to about 25% with hardware acceleration disabled.

Overclocking

Unfortunately, the H55 motherboard Intel provided us with does not have any overclocking features. Once we get updated drivers for our P55 boards, we’ll see how far we can take the Core i5 661.

Power Consumption

Our power meter broke during testing, and I was unable to replace it in time for this review. Hopefully we’ll have a new one to use soon!

Conclusions

I think the best way to look at Clarkdale, is to look at it as a CPU and CPU/GPU separately.

Strictly as a CPU, it has its pros and cons. On one hand, it is clocked quite high (the i5 670 can reach up to 3.73 GHz with Turbo fully engaged – faster than any other Nehalem CPU) and the AES instruction set certainly gives it a huge boost when put to use. Because of this, applications which use less threads will perform quite well. For “overall power” (web browsing, office apps, video games, etc) the dual core Core i5’s are quite good.

But despite having HyperThreading to help things along, the dual core design holds it back in ‘pure calculation’ applications. Things like video encoding, 3D rendering, and file extraction are significantly slower than similarly priced competition.

Considering that putting together a full system costs not much less than a Core i5 750 with a GPU, and slightly more than a Phenom II 965 with an IGP, I don’t see much reason to recommend it to most people. The Phenom II 965 paired with a 785G motherboard will probably be a better option than a Core i5 6xx paired up with an H55 mobo. Especially with useful features like Hybrid Graphics (where you can later add a discrete GPU and still make use of the IGP for power saving and CrossFire) and SidePort (which integrates some memory onto the board, so you can leave your system RAM alone when using IGP).

As far as the CPU/GPU combination goes – all the benefits from that go directly to Intel. It really doesn’t matter to the end user that they moved it over to the CPU – you still have to buy motherboards with a compatible chipset, and those boards aren’t guaranteed to be any cheaper than competing IGP boards anyway.

The real intriguing story is how the Core i3 performs. While the $200 660 didn’t impress me, the $150 Core i3 might. Since it will be competing with the Phenom II X4 925 and X3 720, it might have the opportunity to stand out a bit, with its large, fast cache and relatively high clock speed. Or maybe it’ll get crushed too; it’ll eventually have to contend with the upcoming Phenom II X2 555 (AMD’s fastest Dual Core ever) and 800-series chipset with its Radeon 5000 series GPU.