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Building my Hackintosh - Part 1: CPU Analysis

This is a first article in the Building My Hackintosh series. This article discusses the choice of CPU in a new PC system, with price-performance analysis and recommendations.

AMD or Intel?

When approaching a new machine build, one of the obvious decisions is the CPU manufactory - AMD or Intel. The brand will affect the motherboard directly, as motherboards are designed for a particular CPU brand and socket type.

Usually, this choice is rather simple, and would be most influenced by taste and cost optimization concerns. In my case, building an OSX86 setup introduces more constraints. Initially, only Intel CPUs were supported by OS-X - but as time passed, unofficial AMD support started to appear.

From a superficial browsing of the hardware compatibility page at the osx 86 project, although the page actually shows support for both AMD and Intel, I decided to reduce the risk and go with Intel - based on the assumption that an Intel-based Hachintosh might have less snags and will be more robust then AMD.

Which Socket Type?

CPUs come with different physical pin layout and shape, which traditionally is referred to as ’socket type’. There are several types for AMD, and some for Intel.

I chose socket AM2 for AMD, and LGA 775 for Intel. I wanted to choose a socket that has enough CPUs, and has at least a few years of possible upgrades.

Which CPU Has The Best Value?

Choosing a CPU for your PC should be pretty simple: Pick the fastest CPU you can afford. This would have been the right tactic if the CPU price / performance would have been linear - ideally, spending double would give you double the performance.

In practice, though, the more expensive the CPU the less incremental value you get from it - as you will see in a minute. In addition, some CPU families are not on par with others, and would give less bang for the same buck. Finally, market trends and price wars (which cause the CPU prices to drop on a monthly basis) cause constant flux in the elusive “value” proposition.

In order to reach an analytical decision, one needs to compare two things: The CPU performance vs its current price.

To get the CPU performance, I searched a bit and found several comprehensive performance reviews of AMD and Intel CPUs. A good start is the recent excellent CPU performance analysis on Xbit, which has an extensive set of benchmarks and excellent analysis. To get a normalized performance number I averaged the Xbit performance numbers across the range of applications and benchmarks - as it gives a good approximation of real-use performance.

As for the cost, I simply used NewEgg as the only source. My experience with NewEgg is that its very rare to find a reputable merchant with lower prices across the board - and usually the price difference will be marginal.

Here are the results, in a graph reflecting the prices as of July 13 2007.

AMD CPU Comparison

Brand	CPU	Performance	Cost	Value	HTPC Notes
AMD	AMD 6000 Windsor 3.0 GHz	1.62	$170	8.31
AMD	AMD 5600 Windsor 2.8 GHz	1.53	$150	9.87
AMD	AMD 5200 Windsor 2.6 GHz	1.43	$130	10.21
AMD	AMD 5000 Windsor 2.6 GHz	1.40	$120	10.29
AMD	AMD 4800 Brisbane 2.5 GHz	1.32	$110	11.48	Supports HD w/o OC with GeForce 7x00 / 8800 / IGP. "The perfect HTPC CPU for the AMD Platform"
AMD	AMD 4400 Brisbane 2.3 GHz	1.23	$92	13.23
AMD	AMD 4000 Brisbane 2.1 GHz	1.14	$70	14.43
AMD	AMD 3800 Windsor 2.0 GHz	1.15	$66	17.16
AMD	AMD 3600 Brisbane 1.9 GHz	1.06	$61	17.10	Enough for HD only if you have GeForce 8600/8500

Intel CPU Comparison

Brand	CPU	Performance	Cost	Value	HTPC Notes
Intel	Intel E6600 Conroe 2.4 GHz	1.68	$222	7.53	Supports HD w/o OC with GeForce 7x00/8800
Intel	Intel E6420 Conroe 2.13 GHz	1.52	$186	8.17
Intel	Intel E6320 Conroe 1.86 GHz	1.37	$164	8.30
Intel	Intel E4400 Allendale 2.0 GHz	1.36	$139	9.78
Intel	Intel E4300 Allendale 1.8 GHz	1.26	$119	10.77	Supports HD with OC with GeForce 7x00/8800. See OC Guides - Intel
Intel	Intel Pentium D 935 LGA 775 Presler 3.2 GHz	1.06	$105	10.10
Intel	Intel Pentium D 925 LGA 775 Presler 3.0 GHz	1.00	$89	11.24

Analysis

The CPU costs dropped dramatically in the last 6 months, and continue to slide on a weekly basis. In addition, with the latest price drops on AMD CPUs in the last two months, and as of July 2007 the map seems very interesting. It is also very interesting to note how linear the price-performance graph had become. Half a year ago I did a similar research, and back then the graph looked like a banana - fastest CPUs where much more costly then their relative gain.

In general the graph exposes clearly that AMD CPUs have a clear edge in out-of-the-box cost-performance over Intel CPUs. In other words - if you need to choose between AMD and Intel on price alone, AMD clearly outperforms Intel on any price point.

However, what is not shown in this table is the overclocking performance. I have not covered CPUs more expensive then $250 in this graph (personally I am interested at value deals, and not the super expensive options), but as can be found towards the end of the Xbit analysis, the following fact is revealed: If you overclock (and invest in the appropriate fast motherboard and memory), the Intel CPUs across the board have much more performance to scale then the comparable AMD CPUs.

Apparently Intel CPUs have a lot of room for overclocking, whereas AMD CPUs wont see as much gain in performance from overclocking. My theory (or guess) is that AMD crank every bit of juice from their CPUs (”factory overclocked”?), which explains their good out-of-the-box price-performance, and also the relative lack of overclocking gain. On the other hand, if you want to overclock your system, you will find that the Intel CPUs tend to have much more oomph, which leads to higher performance and value for those chips. The conclusion is that for a high-end overclocked system you would probably want to choose an Intel CPU over a similarly priced AMD CPU.

AMD Picks: AMD 3800

Amazingly, after many fluctuations and adjustments the AMD lineup is clean and linear. For every price-point you get a competitively priced CPU. The notable bad exceptions are the 3600 and 4000, which are both weaker then the 3800 - which in turn becomes the entry-level CPU of choice. Moreover, getting such a performance for less than $70 is hard to beat; for example, doubling the cost will get you the 5000, which is only 20% faster.

If you plan to use the CPU for HD playback, according to this excellent AVS Forum article the 3600 (and obviously the 3800) will power HD playback only if you have the newest graphic cards with HD acceleration, like the GeForce 8600/8500. If you have an older graphics card like the GeForce 7×00, 8800 or an on-board integrated graphics card, you will need the AMD 4800 for smooth HD playback.

Intel Picks: Intel E4300

On the Intel side the scene is stranger and more interesting. Looking at te graph its clear that the Pentium D chips are considerably sub-par to both the other Intel CPUs and comparable Intel ones. I think we can safely discard them from the discussion. Actually, from price-performance perspective we can also safely ignore the E6320 and E6420, which are much more expensive then what their value should be. We are left with E4300 and E4400 (and E6600 at the high-end, for those seeking the highest performance at any cost). Between the two, the E4300 has the best value (performance per Dollar).

HTPC Specific Recommendations

Picking a CPU for your HTPC box is dependent on the graphics card. The reason is that a strong enough graphics card will offload the H.264 encoding strain from the CPU, and allow smooth HD playback even with a relatively slow CPU.

GeForce 8600/8500 : AMD 3800

This graphics card offloads 100% of the CPU work for HD decoding. In this case, even a single core CPU will do - but for VC-1 decoding you still need a dual core CPU, and the AMD 3800 is the best bang for othe buck here.

GeForce 7×00/8800 / On-Board Graphics : Overclocked Intel E4300

With a mid-range graphics card, you need enough CPU juice to decode HD without hiccups. If you want a low-cost CPU, you need to overclock your system to get the performance you need - and the best overclocking cost-performance comes from the Intel chips.

GeForce 7×00/8800 / On-Board Graphics : AMD 4800 / Intel E6600 (no overclocking)

This CPU is up to the task of presenting HD with no hiccups, even with a mid-range graphics card. Alternatively, if you want to use Intel, you would need to pick the Intel E6600.

Now we need only to wait for the next AMD architecture, K8, and see how would this disrupt the battlefield…

References

• CPU performance analysis on Xbit
• AVS Forum HTPC Hardware Recommendations
• NewEgg - AMD CPUs and Intel CPUs
• osx 86 project