We think it's fair to say that the Bulldozer FX8150 was one of the biggest disappointments we've experienced here at OC3D. Most of us cut our teeth on AMD processors, and we had high hopes that the 8 core behemoth would finally bring AMD back in line with Intel. To say it didn't is rather understating things, but thankfully AMD knew that the FX8150 wasn't remotely living up to expectations and so they returned to the lab to refine the concept.
Having suitably beavered away to smooth off the edges, today sees the launch of the Piledriver FX8350. Based upon the same basic principles of the FX8150, eight big cores and high clock speeds, does the performance match up to its Intel rivals or is the 'two AMD cores = one Intel core' equation still in full effect?
Whenever a new piece of hardware is released the company involved also give a press kit out, which highlights the key features and explains which of the competitors models they expect their product to match up to. For AMD and the FX8350 their key target is the Intel i5-3570K, the Ivy Bridge replacement for the brilliant i5-2500K. Considering this is a quad core CPU with no hyperthreading, it doesn't fill us with confidence that AMD have made an eight core CPU that has the performance of an eight core CPU. However it's worth making a note of, as if AMD state it's a match for the i5-3570K then that is what we shall be largely comparing it to.
Out of the box at 4GHz, and with identical 8MB of cache for both the L2 and L3, there isn't an obvious improvement over the FX8150 so hopefully the under-the-hood changes will bring some extra performance.
Generally speaking the Piledriver die is similarly laid out to that of the Bulldozer. The die has the same layout of cores in the corners with their own L2 cache, and the L3 cache making up the whole of the middle section. at 315mm2 it's the same size as the Bulldozer was too.
AMD are claiming gains of 15% from the FX8350 when compared to the FX8150, and we're going to need to see at least that, especially if it's to compare to the boss of the Intel midrange.
As AMD are continuing to use the AM3+ socket this is more likely to be an upgrade path rather than the basis for a new system. However, as AMD have provided their top-line CPU we wanted to ensure that we gave it every chance of blowing our socks off and to that end we're using the enthusiast Gigabyte UD7 990FX motherboard, as well as some blazing memory and speedy SSD.
AMD Piledriver FX8350
Catalyst 12.8 Drivers
Corsair 2666MHz Dominator Platinum
Corsair Neutron GTX SSD
Windows 7 Ultimate x64
As always with AMD overclocking it's a case of finding the fastest available Northbridge and FSB frequency and then balancing the CPU multiplier and FSB until you attain a nice and stable overclock. Starting with the Northbridge we attained 2.6GHz, which is a decent start.
The FSB topped out at a fairly disappointing 275MHz. This will give us enough room to play with though. Leaving the FSB at 200MHz and playing with the multiplier (and some serious vCore) enabled us to attain a 5GHz screenshot, even if the system was so unstable you couldn't do anything with it.
Thankfully there wasn't much tweaking needed to reach a stable overclock, although we are always surprised quite how much voltage is necessary to obtain stability. 4.8GHz is a 600MHz overclock, and exactly the same speed as we generally obtain on all of our Intel CPUs, so we really will be comparing like for like here.
A bit of a mixed bag to start off with. The FX8350 is a little better than its FX8150 dad, and just edges ahead of the i5, but it's hopelessly outgunned in the PhotoWorxx test, with even the 1095T proving a match.
zLib speeds are excellent and a league ahead of the FX8150, as well as being a good distance better than the i5-3570K. AES performance is nothing less than shocking. The AIDA64 tests are definitely a tale of two halves.
Memory performance is frankly abysmal. A 4.8GHz eight core CPU with 1866MHz memory gets trounced by the little 2.8GHz i3-2300, let alone the i5-3570K that AMD claim the Piledriver is targetted against. Memory bandwidth has never been an AMD strong-suit, but this is risible.
The press blurb explains how fantastic the FX8350 is at calculation-heavy tasks, and maybe it is (we'll see on the next pages), but the amount of bandwidth available is farcical. When a stock clocked quad-core can nearly double the bandwidth, you've got problems that mere clock speed can't overcome.
Luckily for AMD SiSoft Sandra is great at separating the CPU from the rest of the system, so if it has stunning calculating abilities we'll see them here. And, surprisingly, we do. The FX8350 is a decent improvement on the FX8150 and is a step ahead of the i5-3570K.
You would imagine that such calculative prowess would bring mind-blowing scores when rendering, but of course you have to take into account the woeful memory performance. So, in the end, the FX8350 is a bit better than the FX8150, a bit better than the quad-core i5-3570K, but left for dead by any current Intel processors. Even the i7-2600K whips it handily.
There are two parts to the POV-Ray test. The average result tell you how fast the whole system works, and the Per CPU gives a decent indication of how efficient each core is. So if we compare the two CPUs that AMD want us to compare, one i5 core is worth 378 PPS, whereas a single AMD FX8350 core is only able to give 218 PPS. Our 'two AMD for one Intel' still holds true.
PC Mark Vantage
Remember how we said that the Memory performance is so bad that it will affect the whole system? Compared to any Intel product the FX8350 is just terrible in PC Mark Vantage. A stock quad core i5-3570K annihilates the 4.8GHz overclocked FX8350. Sure the FX8150 is much worse, but that's not saying a lot.
PC Mark 7
Things aren't quite as bad in PC Mark 7, but the FX8350 is still the poorest performer in the graph.
We're testing 3D Mark at both Performance settings, which will show how well the CPU helps, as well as Extreme, which will be more about the GPU and will mainly highlight any problems with PCI lanes.
In both Vantage and 11, the P score backs up the rather average performance we've seen from the CPU so far. In Vantage the FX8350 is around 3000 points lower than the Intel i5. With the detail upped to Extreme there is still a thousand points between the FX and i5, even though the HD7970 does its best to level the playing field. 3D Mark 11 is closer with only 600 odd points between the two chips, and the Extreme preset actually sees the FX8350 up there with the best of the rest.
3D Mark Vantage
3D Mark 11
Finishing up with the pure calculations of wPrime95, the FX8350 once again shows that its math ability is not bad at all, relative to the rest of the results we've seen, but it doesn't stand a chance against anything with hyperthreading.
Much is made of the efficiency of the AMD CPU's and we wouldn't want to dismiss the performance if it's capable of happening at a vastly reduced power draw. So we've tested the draw of the whole system at the wall when the CPU alone is loaded, and when everything is being used, in both stock and overclocked settings.
There is no doubt at all that the FX8350 is a power hungry beast. It draws 70W more at stock than the Intel at stock, and the overclocked Intel doesn't draw much more than at stock. With everything overclocked and under load the AMD uses 24% more power!
We are big fans of AMD here at OC3D. Not only did we start with AMD CPUs back in the Thunderbird days, but as people who like technology in all forms it's important that all the major manufacturers have healthy competition. Just as the Pentium III was outclassed by its AMD competition, the roles have been reversed for a few generations now. When we reviewed the FX8150 we gave it a justified kicking. Now the refined and reintroduced Piledriver FX8350 is here, is it any more worthy of a recommendation? After all, we were willing the FX8350 to be brilliant and gave it every chance to shine.
Sadly though, we're not convinced it twinkled, much less shined. There are a few bright points though, so let's get all the bad stuff out of the way first.
Comparing processors is always about the freshness of the architecture as much as it is about pure numbers. A 3GHz Q6600 isn't a patch on a 3GHz Ivy Bridge CPU for example. Never more has this been the case than with the AMD FX range. Sure it might be an eight core processor, but those eight cores are only worth four Intel ones. That's largely why AMD compare the FX8350 to the i5-3570K.
The architecture that underpins the FX definitely has some problems though. We aren't asking that the memory has the same performance of the Ivy Bridge, although it would be nice, but we'd at least like it not be so utterly devoid of bandwidth that it drags the whole system down. Even with 2666MHz memory installed we couldn't get it to post let alone run 1866MHz.
Performance in general is nowhere near what we'd expect. In an extremely limited number of tests the FX8350 proved itself as an admirable performer. zLib compression, wPrime, all the CPU calculation heavy tasks were handled to a decent level. Once you require the memory to handle parts of the calculation process though things fall down again. You'd expect, when looking at the math results, that rendering would be a cakewalk. Yet because it's so intensive the bandwidth just cannot keep up and the performance suffers. The general tasks tested by PC Mark show how the FX8350 has improved greatly on the FX8150, but is nowhere near the level of the comparable Intel products.
The only place it did okay was in intensive gaming at high resolutions, where the CPU and memory performance matters less than GPU power.
Which is, at the end of it all, about the size of it. We used the very best possible setup to give the FX8350 every chance of proving its worth. If you've already got an ageing AM3 setup, then the FX8350 is the best option available as a decent upgrade for a decent price. If you are looking to upgrade a full system then it's impossible to recommend. It's too slow, it draws too much power, it's too hot. It's just not worth it.
We so wanted this to be a return to form for AMD. This is the best they have to offer, and they are still a mile behind the competition. If you've already got an AMD setup and can only afford a CPU upgrade then this is just worthy of our OC3D Bronze award. For everybody else, steer well clear. For AMD, start with a fresh sheet of paper.
Thanks to AMD for providing the FX8350 for review. Discuss your thoughts in the OC3D Forums.