The Bulldozer Review: AMD FX-8150 Tested
by Anand Lal Shimpi on October 12, 2011 1:27 AM ESTFinal Words
In many cases, AMD's FX-8150 is able to close the gap between the Phenom II X6 and Intel's Core i5 2500K. Given the right workload, Bulldozer is actually able to hang with Intel's fastest Sandy Bridge parts. We finally have a high-end AMD CPU with power gating as well as a very functional Turbo Core mode. Unfortunately the same complaints we've had about AMD's processors over the past few years still apply here today: in lightly threaded scenarios, Bulldozer simply does not perform. To make matters worse, in some heavily threaded applications the improvement over the previous generation Phenom II X6 simply isn't enough to justify an upgrade for existing AM3+ platform owners. AMD has released a part that is generally more competitive than its predecessor, but not consistently so. AMD also makes you choose between good single or good multithreaded performance, a tradeoff that we honestly shouldn't have to make in the era of power gating and turbo cores.
Bulldozer is an interesting architecture for sure, but I'm not sure it's quite ready for prime time. AMD clearly needed higher clocks to really make Bulldozer shine and for whatever reason it was unable to attain that. With Piledriver due out next year, boasting at least 10-15% performance gains at the core level it seems to me that AMD plans to aggressively address the shortcomings of this architecture. My only concern is whether or not a 15% improvement at the core level will be enough to close some of the gaps we've seen here today. Single threaded performance is my biggest concern, and compared to Sandy Bridge there's a good 40-50% advantage the i5 2500K enjoys over the FX-8150. My hope is that future derivatives of the FX processor (perhaps based on Piledriver) will boast much more aggressive Turbo Core frequencies, which would do wonders at eating into that advantage.
AMD also shared with us that Windows 7 isn't really all that optimized for Bulldozer. Given AMD's unique multi-core module architecture, the OS scheduler needs to know when to place threads on a single module (with shared caches) vs. on separate modules with dedicated caches. Windows 7's scheduler isn't aware of Bulldozer's architecture and as a result sort of places threads wherever it sees fit, regardless of optimal placement. Windows 8 is expected to correct this, however given the short lead time on Bulldozer reviews we weren't able to do much experimenting with Windows 8 performance on the platform. There's also the fact that Windows 8 isn't expected out until the end of next year, at which point we'll likely see an upgraded successor to Bulldozer.
So what do you do if you're buying today? If you have an existing high-end Phenom II system, particularly an X4 970 or above or an X6 of any sort, I honestly don't see much of a reason to upgrade. You're likely better off waiting for the next (and final) iteration of the AM3+ lineup if you want to stick with your current platform. If you're considering buying new, I feel like the 2500K is a better overall part. You get more predictable performance across the board regardless of application type or workload mix, and you do get features like Quick Sync. In many ways, where Bulldozer is a clear win is where AMD has always done well: heavily threaded applications. If you're predominantly running well threaded workloads, Bulldozer will typically give you performance somewhere around or above Intel's 2500K.
I was hoping for Bulldozer to address AMD's weakness rather than continue to just focus on its strengths. I suspect this architecture will do quite well in the server space, but for client computing we may have to wait a bit longer for a more competitive part from AMD. The true culprit for Bulldozer's lackluster single-threaded performance is difficult to track down. The easy answer would seem to be clock speed. We've heard of issues at Global Foundries and perhaps Bulldozer is the latest victim. If AMD's clock targets were 30% higher than Phenom II, it simply didn't make them with the FX-8150. I've heard future derivatives will focus more on increasing IPC indepedent of process technology and clock speed, but if you asked me what was the one limit to success I would say clock speed. As a secondary factor, AMD appeared to make some tradeoffs to maintain a reasonable die size at 32nm. Even then Bulldozer can hardly be considered svelte. I suspect as AMD is able to transition to smaller transistor geometries, it will be able to address some of Bulldozer's physical shortcomings.
The good news is AMD has a very aggressive roadmap ahead of itself; here's hoping it will be able to execute against it. We all need AMD to succeed. We've seen what happens without a strong AMD as a competitor. We get processors that are artificially limited and severe restrictions on overclocking, particularly at the value end of the segment. We're denied choice simply because there's no other alternative. I don't believe Bulldozer is a strong enough alternative to force Intel back into an ultra competitive mode, but we absolutely need it to be that. I have faith that AMD can pull it off, but there's still a lot of progress that needs to be made. AMD can't simply rely on its GPU architecture superiority to sell APUs; it needs to ramp on the x86 side as well—more specifically, AMD needs better single threaded performance. Bulldozer didn't deliver that, and I'm worried that Piledriver alone won't be enough. But if AMD can stick to a yearly cadence and execute well with each iteration, there's hope. It's no longer a question of whether AMD will return to the days of the Athlon 64, it simply must. Otherwise you can kiss choice goodbye.
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Pipperox - Saturday, October 15, 2011 - link
With a 40-50% gain Bulldozer would be even ahead of Ivy Bridge.. and what comes next.Or are we still talking about SuperPI?
Or games run at 640x480 lowest quality settings?
The fact is, almost all single threaded applications are old and they run already super fast on ANY cpu and the difference can be seen only in benchmarks.
All recent performance demanding applications are properly multithreaded, and Bulldozer there is competitive with i5 2500 and occasionally with i7 2600 (and with a 10% boost Bulldozer would be competitive with i7 2600).
And this will become more and more the standard one year from now.
Sure Bulldozer has not met the enthusiasts' expectations, it doesn't perform as people would expect an "octacore" (but it's not, it's just a quad with a different form of hyperthreading and "clever" marketing) and it doesn't deserve the FX moniker.
But still it's the most competitive CPU AMD has launched in years, perhaps with the exception of Zacate.
nirmv - Saturday, October 15, 2011 - link
Not all applications are heaviliy multi-threaded, there is still need to improve single thread performance.And even for those few loads that are competitive in performance, they do it with twice the power draw.
See here from xbitlabs review :
http://www.xbitlabs.com/images/cpu/amd-fx-8150/pow...
Pipperox - Sunday, October 16, 2011 - link
But increasing single threaded performance has a cost, on die space and circuit complexity.Bulldozer has a huge die just because it has enormous caches (8MB L2 vs 1Mb on SandyBridge) which probably will turn useful on server workloads (but that's just a guess).
By looking at the die shot, you'd get a 40% die area reduction with "normal" caches.
So AMD engineers decided to drop single threaded performance improvements in favor of higher multithreaded scalability and higher clock speed scalability.
We'll see if in the long run this will pay off.
I agree power consumption doesn't look good in comparison with Intel, but it does look good in comparison to Thuban.
This is the first released silicon of Bulldozer.. i expect power consumption to improve with newer steppings and silicon process tuning.
That being said, Intel has the best silicon process in the whole industry.
AMD can't compete with that.
But i'd guess that at lower clock speeds (like in server), AMD's power consumption will improve a lot.
Looks like with the FX AMD tried to push their current silicon to the maximum which they could (within the 125W TDP which is sort of an industry standard).
LiveandEnjoyLife - Friday, October 14, 2011 - link
Some people are missing the point. At this stage in the game, processor speed is a moot point beyond benchmarks. AMD and Intel make very fast CPUs in relation to what gamers and every day users use them for. Intel CPUs are blazing fast and AMD CPUs are fast. The average Joe does need more than a dual-core CPU. If you were going to actually do something that would require heavy multi-threading, then it comes down to the efficiency the app to make use of the cores and the ability to use hyperthreading. If you wanted the most performance for a mult-threaded application, you would pick more physical cores over virtual cores. So for most of use it comes down to bang for buck.8 cores is better than 2, 4, or 6 for true multi-threaded capable applications.
For speed tests Intel wins hands down.
If you were sitting next to someone playing a game and all things were the same except CPU, you would not be able to tell which machine is running what CPU. However you would notice if one costs significantly more than the other.
That is my 4 cents.
7Enigma - Friday, October 14, 2011 - link
Hi Anand,Great review but there is a text error when referring to pass one vs. pass two of the benchmark mentioned in the Subject line. You said:
"The standings don't change too much in the second pass, the frame rates are simply higher across the board. The FX-8150 is an x86 transcoding beast though, roughly equalling Intel's Core i7 2600K. Although not depicted here, the performance using the AMD XOP codepath was virtually identical to the AVX results."
But the graph clearly shows a complete flip-flop from first pass to second pass. When I look closely it appears you ordered the text and graphs differently and were referring to if you had the non-AVX and AVX-enabled graphs next to each other instead of in separate sections. Basically the text and graphs don't match up.
HTH
Iketh - Friday, October 14, 2011 - link
You're an utter retard. The reason they're sold out is newegg advertised these nicely all over their site, including the front page, with "World's first 8-core desktop processor."There are plenty of reasons to purchase these processors aside from their performance and that's ok. But the majority bought them thinking they're gonna "rock", and those are the ones "showing intelligence." Same goes to you for thinking the majority is well-informed/intelligent.
What's even worse, the 8-core version for sale is the 3.1ghz, not the 3.6 tested in this review. I'm seriously LOL'ing...
How many did Newegg have in stock anyhow? Wouldn't that figure matter regarding your ignorant comment?
rcrossw - Friday, October 14, 2011 - link
I have used AMD products for years. I use Intel at work. So to me there is no real difference between the two for what Business and the Average Computer user want or expect.Does it run, does it do the work I require of it, and do my programs and Network Access
work well and are reliable?
Intel indeed has incredible Processors, fast and reliable, and in the high end - expensive.
AMD is Low and Mid range - with processors that the average person can afford. Who is the most innovative - both. Today Intel has been , now I think the user needs to give this New X86-64 Architecture a chance.
I have a Asus M5A99x EVO with an FX6100 installed. The only problem I have had is having to upgrade the BIOS to accept the new Processor. So far I have had the Processor to 4.2 Ghz. Though AIDA 64 caused a BOD on one test. At 3.8 Ghz runs like a champ. Stil
working back to as close as I can get to 4.2 on Air.
After three years I have retired my old Phenon II Tri Core 720 for this, and it works for me.
I am not an extreme gamer, etc. But test it your self, before being too overly critical.
Does it work for me.
As an aside, next a SSD for faster response.
For those interested:
Asus M5A99x MB BIOS 0810 ( Newest)
AMD FX 6100 at 3.8 ghz
Corsair Vengeance 1600 - 16 gigs
HIS Radeon HD 6850
Windows 7 Ulimate 64
HPLP2475W Monitor at 1920x1200 DP
WD 500 SATA
WD 1001 SATA
LG H20L BD-R
Plextor DVDR
Enermax 620 Liberty PS - I know old but works.
Thanks
davbran - Saturday, October 15, 2011 - link
I have been having a hard time writing a comment on this topic without drawing fire from trolls.This review is hogwash without more information.
If the hardware is the same on all test machines, apart from the CPUs, then there is no wonder the performance was so bad. 6 Cores are going to utilize, and I am just pulling a number out of my ... hat, 4gb of RAM more efficiently than an 8 core using simple kitchen math. No need to break out the slide rules. It's a known fact, to most, that the big bottleneck in the multicore/multiprocessor world is memory. Mind you that's if we are factoring in that all the code that was used for testing purposes was written with multi-threading in mind.
You just can't compare apples to bananas in this manner.
silverblue - Saturday, October 15, 2011 - link
Each to their own. I thought it was a pretty good review, and Anand certainly held back from slating AMD to hell.Iketh - Sunday, October 16, 2011 - link
LOLLLLL