It seems an eternity ago now that we first heard about the Bulldozer processors from AMD.
Indeed we've been expecting them for so long that it was six months ago when we reviewed the first 990FX board that was all ready for the next generation of CPUs, but finally the wait is over and we have our hands upon the the premium, top of the range, flagship AMD Bulldozer processor, the eight core FX8150.
Yes this is the first 8 core CPU that we've had the pleasure of testing. Despite the huge amount of cores this is being priced and marketed directly at the Intel Core i5-2500K. Given our large experience with this chip and the fact that the FX8150 has twice the amount of cores and a much faster clock speed, we're expecting a slaughter.
We know you can't wait to see how it goes so let's crack on. We've a lot to get through.
Before we get to the new architecture, there is a range of CPUs coming out to fill every niche from the bargain basement to the enthusiast. You can see that our top range FX8150 not only has 8 cores to play with, but a whopping 8MB of both L3 and L2 cache, as well as a Turbo mode that puts it past 4GHz. Highly impressive numbers we are sure you'll agree.
The big revolution in the layout of the Bulldozer processor is the way in which the cores are laid out. Whereas with the current LGA1155 Intel CPUs, and the current AMD Phenom CPUs, we have the cores across the top and the cache beneath, here the cores are split up into modules of two cores each. Each of those modules then has 2MB of L2 cache to call upon all to itself.
One thing that has been hammered home in the AMD documentation and conference calls is how the Bulldozer range, and specifically the FX8150 we have on test today, is aimed directly at the Core i5-2500K. Considering that we currently rate the 2500K as the best all-round processor on the market, it's a serious statement of intent from AMD.
Even a cursory glance at the table below shows how, in pure number terms, the FX8150 has the beating of the Sandybridge range. Larger cache, more cores, higher native memory speed support, faster turbo and extra instruction sets. If performance can be judged solely on paper, then this should be a demolition.
One slightly curious decision is the one to compare the system price of the FX8150 against the mental i7-980X. We know that the 980X is staggeringly pricey, but equally in terms of gaming performance the humble i5-2405S wasn't put in the shade. However, this is why we review things to see where the truth is amongst the hyperbole.
Now we've finally got the Processor it was designed for we can utilise the 990FX equipped Crosshair V to it's full potential. Otherwise it's our universal test-setup to ensure we can compare as like-for-like as possible.
For our tests we're going to be running the FX8150 primarily against its forebear the Phenom X6 1095T and it's target, the Sandybridge Intel line.
AMD Bulldozer FX8150 CPU
ASUS Crosshair V Formula
8GB Mushkin Redline
Corsair AX1200 PSU
Noctua NH-D14 CPU Cooler
Samsung Spinpoint F3
Windows 7 x64
The FX8150 is able to be overclocked using the excellent AMD OverDrive software. It's nice to see 8 cores ready to rock and roll.
As with all AMD overclocking it's worth finding the maximum Bus Speed, and with the FX8150 installed the Crosshair V gave us 325MHz. It's worth noting that when we reviewed this motherboard back in May with the 1095T installed it hit 350MHz. However it was capable of pushing our Mushkin Redline just past the 2000MHz mark whilst still retaining reasonably tight 9-9-9-27 timings.
Much is made in the press notes and advertising about this being the fastest processor on earth. However AMD were at pains to mention that to get this chip on to and past 5GHz you had to disable most of the cores. This seems pretty pointless to us as the whole point in having a 8 core CPU is to have 8 cores. If we wanted a dual-core we'd buy one and save a fortune. Despite this, and a hell of a lot of faffing about later, we managed to obtain 5GHz with all 8 cores enabled. I am the first person to admit that I love a complex overclocking session but this just felt like a chore. Give me the 1090 anyday over this.
There is a very good reason why AMD recommend disabling cores when on air, and even supply the FX8150 with water-cooling in some markets, it's toasty! There is no way we could run our 5GHz overclock as even a Delta strapped to our NH-D14 couldn't keep it cool enough. Disabling 3 of the Bulldozer modules (6 cores) we managed to obtain 5.2GHz, so there is a little to be had for cutting back if you're only interested in the big MHz number.
For out benchmarks we settled on 4.695 GHz which, as you can see from the screengrab below, still provided a pretty warm 76°C its also worth pointing out that AMD are famed for crappy temperature probes. I can honestly say that the Noctua NH-D14 has NEVER felt warm to the touch and been kicking out so much heat with a CPU temperature of just 76c. I would honestly have thought it was closer to 90 - 100c. Something has to be up when at stock and idle its apparently 9c, that's 11c below the ambient temp.... Impossible without a fridge!
The Stock results certainly don't blow us away. Although there is a lot of extra performance in the zLib testing, the CPU Queen and PhotoWorxx results, even when overclocked, only just edge a stock i5-2500K and are put in the shade by the overclocked 2500K. Not an auspicious start.
The Memory benchmarks are a clear improvement over it's predecessor the 1095T, but nowhere near as good as anything on a LGA1155. The write speeds in particular are poor at best.
The extra beef of the 8 core FX8150 pays some dividends in the Dhrystone and Whetstone tests in Sandra, although nothing as spectacular as one would expect from twice the cores. Indeed the hyperthreaded i7-2600K decimates it.
Comparing solely against the FX8150s intended competition it's only really the Integer x16 benchmark that sees any significant benefit. What are those other four cores doing?
CineBench is a perfect multi-threaded application and we should finally see the FX8150 start rocking out. Except we don't. Once again the Quad Core i5-2500K is perfectly able to match the Octo Core FX8150, and the hyperthreading on the i7-2600K is in another league altogether. Theoretically hyperthreading shouldn't be as good as a genuine core.
PC Mark 7
For PC Mark 7 we're not using the Intel Rapid Storage Technology as it would obviously skew the graph greatly in favour of the i5-2500K. Even without it the Sandy Bridge CPU is a clear leader on the graph, and the FX8150 needs a serious overclock to pass its two-core lighter predecessor. When the AMD hexcore is keeping up, it's worrying.
The Heaven Benchmark from Unigine is a stronger test of the graphics card than it is the processor, but once again in both zero AA and 8xAA scenarios the FX8150 is woefully short of horsepower. This is getting quite embarrassing.
Extra image quality doesn't lessen the pounding. If this was a boxing match we think a towel might be thrown in about now.
3D Mark 11
Finally the bleeding stops and everything scores around the same in the latest of Futuremarks 3D Mark suites. Although it's worth noting that the non-HT, quad core 2.8GHz Intel i5-2300 and AMD X6 1095T aren't far behind the 4.7 GHz Octocore FX8150.
3D Mark Vantage
Moving back a generation to 3D Mark Vantage, the situation actually deteriorates for the AMD Flagship. Instead of trading punches with the rest of the setups on test, the little i5-2300 and X6 1095T both outscore the FX8150.
Alien vs Predator
Stepping into some real-world gaming, Alien vs Predator starts off with the FX8150 and i5-2500K as near as makes no difference identical.
Far Cry 2
Finally the creaky old Far Cry 2 comes to AMDs rescue. The stock FX8150 is still behind its Intel target, but when overclocked we at last see a win for the Bulldozer.
An AMD partner game and one that can take advantage of every last ounce of CPU horsepower, Crysis 2 has an extra 7 FPS on average when run on the FX8150 instead of the i5-2500K. Little victories.
With everything pushed to the limits with the DX11 and Hi-Res patches installed, the AMD FX8150 just edges ahead by a few frames again. Although their is a stern drop in minimum frame-rate. Still the average is what matters and it's ahead of the i5-2500K.
The Witcher 2 is the most demanding game on the planet, and the extra cores of the FX8150 gain us 3FPS at stock, and 7FPS when overclocked in comparison to the Core i5-2500K.
Finally wPrime95. We'd hope that those extra cores will give us some earth-shattering times, but the 2600K is leagues ahead and the 2500K not very far behind. It's all rather ho hum.
When AMD released the X6 1095T me and VB had a serious argument about how good we thought it was and where it placed in the grand scheme of things. Suffice to say that with the FX8150 there was no such debate. At all.
Bulldozer has been hyped as the next big hope for AMD. The company who, for a lot of us, were the first to bust the 1GHz barrier, whose Thunderbird and Barton processors were the mainstays of our enthusiast lifestyle. Sure the Phenom was a bit average, but with this new chip they knew what the opposition had under their belts and knew exactly what they had to do. Indeed it's be hammered into us relentlessly how this is their shot at beating the Sandy Bridge in every department.
To say we're disappointed is to understate things. It's not that the Bulldozer FX8150 is poor when compared to the LGA1155 processors, it's not good when compared to AMDs own Phenom II X6.
Much has been made of the Bulldozer modules that each contain two cores. Judging from the performance the reason they've called them modules isn't because each one is like a dual-core processor. It's because each one is about the equivalent to a single Intel core. What on earth are they doing? The numbers imply something monumental. It marmalises the Intel on clock speed, cache and number of cores, yet the results show that even the i5-2500K beats it in nearly every test, and the i7-2600K annihilates it to such a degree it's embarrassing. How AMD have the cheek to compare it to an i7-980X in pricing terms is frankly beyond us. If a i5-2500K can make this look merely average, the i7-980X would make it look like something from the stone-age.
In application-based testing the FX8150 just doesn't really get it done, and certainly nothing like it should given its lofty specification. The X6 1095T is just as good and that's older, cheaper and less well-equipped. Gaming results are far kinder and the FX8150 even topped some of our graphs compared to the i5-2500K. On the flip side though the comparitively weak i5-2300 wasn't far behind in newer games and ahead in older ones.
There are few crumbs of comfort. AMDs aim was to produce a hardcore processor that out-performed and was cheaper than the i5-2500K. In actuality the reverse is true. Initial pricing indicates most retailers will sell around the £220 mark, although Aria have it at the cheapest UK price, £190. This is still £20 more than the i5-2500K, and the 2500K comes with the robust Z68 chipset where any motherboard at all can overclock it past 4.5GHz with ease and get identical RAM performing far faster too. Don't forget that this is the Flagship CPU in the new AMD line. The absolute best performer they can muster. We don't know what the processor is doing with 8 cores at 4.2 GHz, but it certainly isn't using them to give the end user any performance.
We cannot overstate how saddened we are by the current state of affairs at AMD. It wasn't that long ago that their CPU arm was producing good-performing great value chips, and their GPUs were high-performance, cool and quiet offerings. Similarly to the hot HD6 series of GPUs the FX8150 is a toasty processor. Whilst we could overclock it to 5GHz you'd need a dedicated dual-rad to keep it usable, and even in our 4.7GHz test state it was making our NH-D14 seriously hot to the touch.
It's less of a Bulldozer, and more of a trowel.
Thanks to AMD for providing the FX8150 for review. Discuss in our forums.