Price Performance Ratio - Which is Best Overall?

In this instance we've taken the relative difference in performance (compared to the cheapest CPU) and divided it by the absolute price of the CPU in question. Below are graphs averaging all the tests we've looked at to get a total performance of the CPU alone, or total platform, per $USD.



In terms of the CPU only, here we see the overclocked Q6600 with DDR3 and DDR2 as the most performance per dollar overall, with the overclocked E8400 with DDR3 not far behind. The overclocked Core i7 920 is not far behind, but the Phenom X4 9850 at 1GHz slower is only half a percent per dollar behind. The AMD CPUs continue their superb trend of price performance as the best value non-overclocked CPUs and quad cores on sale today, with the Intel Core 2 Duo E8500 and Core i7 920 only a bit behind this. Generally the Intel quad cores without overclocking don't provide as great value and the relative value drops right off very quickly.

When we look at the entire platform though the Q6600 wins the day by a couple of percent. In addition to its overall better performance than the overclocked Phenom X4 9850 and it's certainly the platform of choice, but for those who want extreme value the overclocked AMD platform is certainly the one to consider.

Again, the non-overclocked AMD platforms provide the best bang-per-buck, and the high cost of the Core i7 platform offsets the relative value despite the supreme performance of the Core i7 920 - with a cheaper motherboard and using cheaper memory the Core i7 920 will clearly become the platform of choice since there's not much more you can save on the AMD platform. The important thing to note here is that on the Intel front, without overclocking the Core i7 920 is better value than all the Intel CPUs - that even includes the overclocked Q6600 and E8400 on the DDR3 platforms as well! The Intel DDR2 platforms clearly outweigh the DDR3 still in price performance too.

Price : Performance Value Conclusions

Without overclocking we have to say that AMD provides the better value platform and generally better value CPUs compared to Intel's current Core 2 range. If you were just simply interested in squeezing every last penny out of your purchase, these are the platforms to go for. While the Intel Core 2 range performs better, the performance increase doesn't always necessarily warrant the jump in cost.

The E8400 overclocked is also very good, as is the AMD Phenom X4 9850 at 3GHz - both make great value purchases in a similar budget, although both have different performance strengths. The E8400 is great in games and is a single threaded monster, however the Phenom X4 provides a very cheap multi-threaded cruncher. However, unfortunately for AMD, if you want multi-threaded munching on the cheap we're back to the Q6600 with DDR2 again.

AMD should take away the positive result that while in a direct performance comparison it'll lose out to Intel's Core 2 range, most of Intel's current quad line-ups are clearly too expensive and provide a negative relative value for money.

Surprisingly enough, despite the high platform cost of triple-channel DDR3 and very expensive motherboards, the increase in performance offsets the Core i7 cost in such a way that they come out with very positive relative value overall and if you can afford one, the Core i7 920, even without overclocking, makes for nearly 40 percent better value than the competition.

While budgets and personal interests in specific price-to-performance values like gaming will dictate not everyone goes out and buys a Core i7 920 tomorrow, it's been interesting to see how relative prices that are often ignored in reviews can severely affect the outcome of getting good value for money. While the Core i7 965 may top many tables and the Phenom X4 9950 may languish at the bottom - when we take what you get for your money into account, the two sit within a two percent relative difference.

Essentially, we could say you're no better off for spending a lot of money on an expensive Core i7, but we've not taking into account an essential equation: time = money. This is an unquantifiable factor, but also one that drives Intel and AMD to make faster and faster CPUs - to get stuff done quicker. In the business world that costs them less because it's more efficient so they can be more productive, while in a home environment the value of time is harder to pin down - a rendering box left overnight costs nothing in time, however if it's the family PC and there's a queue to use it, having a system chugging with a task will only cause arguments. How many of our parents have threatened any amount of money just to shut their kids up?

We hope you can take away something from our numbers and unique approach here, and if you've got an idea to improve or expand on our formulas and conclusions, please drop us a note and instead of talking bit-tech we'll talk bit-math instead!

Addendum 13th November 2008: The Price Performance Ratio graphs above and conclusions were previously calculated wrongly and as such have been changed accordingly.