AMD FX 8150 Black Edition

October marked a special occasion for CPU manufacturer AMD – it released its first completely new processor design since 2003. Athlon 64, for those that remember, heralded the golden age for AMD where by and large its chips matched or beat the performance-per-dollar value of rival Intel’s products.

Three years later Intel’s Core 2 line of processors were released, which sparked the downward spiral which AMD has since failed to pull out of. Their new family of CPUs – known as Bulldozer – is meant to change all that.

The main problem faced by AMD is that instead of meeting Intel head-to-head with high performance hardware, they opted to change tack and focus on the value end of the market, providing low cost CPUs which were incredibly good for low power and low noise situations like Home Theatre PCs and mobile computers.

In the high performance arena their strategy was to release CPUs with many processing cores, with their six core Thuban chips hitting the market at roughly the same time as Intel’s more powerful yet heinously more expensive Gulftown six core processors. Ultimately this didn’t pay off, as consumer applications and games continued to benefit more from higher clock speeds and better CPU architecture rather than having more processing cores to work with.

As if AMD didn’t learn anything from this, their first product announced in the new Bulldozer line up has no less than eight cores. The AMD FX 8150 Black Edition, which we put through the PC World labs this month, is advertised as running at 3.6GHz. However, it’s capable of overclocking itself to 4.2GHz, so at least AMD has bumped up the clock speeds as well, compared to their fastest six core CPU from the Athlon II X6 range (the 1100T) which ran at 3.3GHz stock/3.7GHz overclocked.

The other thing about Bulldozer which is good to note straight off the bat is that it is compatible with all existing AM3+ (and even some AM3) motherboards. This means owners of older Phenom II processors with an AM3+ motherboard who wish to upgrade to a newer CPU can simply drop in a Bulldozer chip with nary a driver update, let alone complete system rebuild (any AM3 motherboards which can support the new chips will likely need a BIOS update at the very least however).

Aside from the FX 8150 there are three other Bulldozer chips which should be on our shelves this month, specifically the 3.1GHz FX 8120, 3.3GHz FX 6100 and 3.6GHz FX 4100 (the first number in the model name indicates how many cores it has). These are all multiplier-unlocked for easy overclocking, and also range between 95W and 125W TDP – expect lower power parts at a later date.

At this point it’s worth mentioning that when it comes to Bulldozer architecture the term “core” doesn’t mean the same as what it meant for older AMD processors like the six core Thuban chips. Where each core in the older architecture had its own resources such as integer and floating point units (two parts which did most of the processing work inside a core), an eight core Bulldozer chip is comprised of four “modules” each of which has two integer cores and one floating point unit.

Effectively this means that each core in a Bulldozer CPU has less resources than an older Phenom II CPU does, however AMD claims that integer cores are much more important than FPUs, so two Bulldozer cores should offer about 80% of the performance of two Thuban cores, whilst offering more performance per watt.

This leaves AMD in a tricky situation as that means that Bulldozer processors should perform at roughly the same level as the older models running at the same clock speed, so hopefully they are able to ramp up the clock speeds in future models to compensate for this.

The FX 8150 processor we received for review came packed with an excellent Asus Crosshair V Formula AM3+ motherboard (as well as a comically large AMD-branded belt buckle, go figure). To test the chip we put it through our standard test suite which consists of the 3DMark 11 gaming and physics benchmark, 7-Zip file compression, PCMark 7 system benchmark, Cinebench R11.5 3D scene renderer and Trackmania Nations Forever gaming benchmark.

For comparison we lined the FX 8150 up against a 3.0GHz six core AMD Phenom II X6 1075T as well as a 3.4GHz quad core Intel Core i7 2600K, which will be its main competitor given the similar price points. The Phenom II X6 1075T is much cheaper than both of the other chips, so hopefully it keeps them on their toes at least.

Completing the test systems are dual AMD Radeon HD 6850 1GB video cards, 2x2GB DDR3-1600 Crucial Ballistix memory sticks and a 40GB Intel X25-V SSD boot drive running the 64bit version of Windows 7 Professional SP1.

In all results apart from the PCMark7 total score, the Intel 2600K completely dominates the AMD FX 8150. Most painful are the 3DMark11 physics, Trackmania and single-core Cinebench results in which the Intel chip pumps out between 40% and 50% greater performance than the Bulldozer. None of these tests utilise multiple cores so it is evident that Intel strongly hold the “performance per core” title, in these select few applications at least.

Looking at the highly threaded benchmarks such as the multi-core 7-Zip and Cinebench tests, the Bulldozer fares much better against the Intel 2600K but still lags about 10% to 20% behind. The AMD chip does manage to pull ahead to gain a higher total PCMark7 score, however Intel still massively outclasses it in the computation score, which is a CPU-intensive subset of the 22 tests PCMark 7 uses to calculate the total score.

Throwing purchase price considerations into the mix, the bargain-basement price of the Phenom II X6 1075T gives it impressive bang-for-buck. Interestingly, the AMD FX 8150 isn’t too far off the Intel 2600K in this regard.

Overall, if you’re considering upgrading from an older six core AMD CPU, I honestly wouldn’t bother considering this first batch of Bulldozers. Nor would I recommend them over the current line up of Intel processors if you’re building a new system.

If you have an AM3+ motherboard and a very slow dual- or quad-core chip, then perhaps it might be worth it, otherwise I say wait for AMD to ramp clock speeds up and prices down before seriously looking at one.