USB 3.0, SATA 6Gb/s, Motherboards, And Overcoming Bottlenecks
Table of contents
- 1. Why PCI Express 2.0 Matters
- 2. Bottlenecks And Solutions For USB 3.0 And SATA 6Gb/s
- 3. Gigabyte P55A-UD6 (Graphics Versus Connectivity)
- 4. Gigabyte P55A-UD7 (Maximum Connectivity And PCIe Switching)
Soon, 4.8 Gb/s USB 3.0 and 6 Gb/s SATA will be hitting the mainstream. But be careful when you buy your next mainstream motherboard; some don't handle these technologies very well. We compare three implementations and recommend best practice solutions.
This happens every few years when bottlenecks start impeding performance, but 2010 will be crowned by internal and external storage device bandwidth leaping forward to the point where we're, yet again, constrained by the speed of media and not a physical interface. SATA 3.0, running at 6 Gb/s, promises faster connectivity to the latest solid state drives and mechanical disks. Outside of the PC, we’ll be seeing more and more USB 3.0-based solutions able to move data at the storage devices’ maximum speed (as you likely already know, USB 2.0 holds back the storage performance of many devices in a big way). Existing bottlenecks will be gone—hopefully.
USB 3.0 and SATA 6Gb/s Hardware
Add-in controllers enabling USB 3.0 and SATA 3.0 have been available for several months, and are now hitting the mainstream (in fact, AMD recently added 6 Gb/s SATA support to its SB850 southbridge). NEC was first to release a full-blown USB 3.0 controller (µPD720200). Cross-compatibility with USB 2.0 is something users take for granted, and we haven’t seen any USB 3.0 hardware that wouldn't work on prior-gen hardware. GDA and VIA offer USB 3.0 hub controllers, and more designs will certainly be following.
The situation is similar with SATA 3.0. Marvell’s 88SE9123 is the dominant add-in component as the storage industry focuses on transitioning from 3 to 6 Gb/s in 2010. However, not all platforms are able to give these higher-throughput subsystems the bandwidth needed to run unconstrained.
PCI Express Bandwidth Issues
The bandwidth issue is a product of chipsets with too little peripheral connectivity and motherboard vendors pressured to include copious value-added functionality. As long as USB 3.0 and SATA 6Gb/s aren’t built into Intel's and AMD's core logic, those controllers remain add-on devices that require an interface with ample throughput. The interface of choice, naturally, is typically PCI Express, which currently spans two generations of technology. PCI Express 2.0 offers 500 MB/s throughput per lane, while PCI Express 1.x is limited to 250 MB/s. Clearly, a single-lane link cannot saturate the 6 Gb/s peak bandwidth of SATA 3.0 or 4.8 Gb/s ceiling specified for USB 3.0. Rated at up to 500 MB/s, a second-gen PCIe x1 interface is considered adequate.
Second-gen PCI Express is most often used in 16-lane links, giving the latest high-performance GPUs ample bandwidth. As far as we know, every mainstream platform offers at least 16 lanes, whether through the northbridge (AMD 785G, for example) or the processor itself (Intel's Core i3 and Core i5 CPUs). Enthusiast chipsets like AMD's 790FX and Intel's X58 Express offer (at least) twice this amount. Unfortunately, all other PCI Express lanes remain at 250 MB/s. There is an interesting difference, though, in how AMD and Intel handle this connectivity.
AMD vs. Intel?
For some reason, Intel's mainstream chipsets only support PCI Express 2.0 on the primary links that are used for graphics. This applies to both LGA 775 and LGA 1156 platforms. While Intel claims PCI Express 2.0 support for its LGA 1156 based PCH, it limits throughput to PCI Express 1.1-class performance. This is naturally a problem when we start looking at the latest high-speed motherboard-down controllers.
AMD, on the other hand, upgraded the link speeds on its 700- and 800-series chipsets, which means that current AMD mainstream and enthusiast chipsets don’t create bandwidth bottlenecks for high-speed add-on devices.
We took three P55 motherboards from Gigabyte and MSI that all come with different solutions to offer USB 3.0 and SATA 6Gb/s connectivity. We analyzed SATA performance using Crucial’s new RealSSD-C300 and a Seagate Barracuda XT with support for the third-gen standard and found that not all solutions deliver ample bandwidth.
Related Stories :
- X58 In 2010: Four LGA 1366 Boards With USB 3.0 And SATA 6Gb/s
- USB 3.0-to-SATA Adapter Gives HDDs SuperSpeed
- ECS Also Providing USB 3.0 and SATA 6Gb/s Cards
- HighPoint to Release PCI-E 2.0 SATA 6Gb RAID
- WD Ships My Passport Ultra USB 3.0 External Drives
- Sitecom Releases Gbit Ethernet Adapter With USB 3.0
- TRENDnet Launches Wireless AC USB 3.0 Adapter
- Scythe Launches Interesting USB 3.0 Based Card Reader
- Silicon Power Intros New USB 3.0 Portable Drive
- Intel Confirms, Fixes Haswell's USB 3.0 S3 Sleep Problems
Unfortunately, Intel is a pain-in-the-a$$ for not picking USB3.0 into their mainstream chip until today.
AMD sure know what they can give consumers first hand on technology that doesn't need to cost as much as Intel motherboard.
Bah... enough of 1156...Its been how many months and still too few X58 USB3.0 boards out there.... what more boards that actually utilize the full 6gb/s.
Its hard to be as patient waiting for the right technology and at the right time to upgrade...
why no AMD based motherboards?
why? many of intel motherbaords are limited to pcie 1.1 speed
why no AMD based motherboards?why? many of intel motherbaords are limited to pcie 1.1 speed
It seems that many of Mr. Schmid and Mr. Roos articles are Intel articles. Not a complaint but just an observation.
Why no AMD boards? It's right there; because current AMD chipsets don't have bandwidth problems:
and:
AMD's best CPUs aren't as fast as Intel's, but if you're just gaming, you probably won't see a difference. The AMD platform, however, is superior unless you're willing to pay for X58.
Even though there is no bottleneck on the AMD platform it would have been ok to post result when it comes to the actual speed difference between these 3 boards and one AMD equipped on .. to see how large is this bottleneck in numbers.
Just my 2 cents on the matter
It puzzles me why no one noticed that when utilizing a single AMD 5850 GPU, the Gigabyte UD6 board actually has the fastest throughput!
I'm actually pretty satisfied with a single 5850 GPU card, which is darn fast and good enough for all the latest games), so buying a Gigabyte UD6 board seems the best choice among the 3 reviewed in this article.
Someone correct me if I'm wrong.
Very informative article. It cleared up some misunderstandings about USB and SATA.
I must be missing something. Even with the switching and PLX device, isn't the bandwidth through the PCIe interface more bottlenecked than the SATA 2.0 interface that is natively supported by the 1156 platform? It would be interesting to see a comparison between the tests done here and the performance of the same drive connected through natively supported SATA 2.0 on the same system.
Can we quit with the AMD fanboy whining already? We dont need to see AMD comparisons in this article but it was very clearly stated MULTIPLE TIMES by the author that there is no bottleneck/performance limitation with AMD platorms. I believe the title of the article is "USB 3.0, SATA 6Gb/s, Motherboards, And Overcoming Bottlenecks" which would indicate that it is covering platforms that have a "Bottleneck" and how to overcome it. So if there is no bottleneck for AMD we dont need to have a review of their parts!!!!
BTW thank you very much for posting this article I am currently building a Media Server/NAS and was tinkering with both AMD and Intel builds. This just pretty much slammed the door on any intel build.
First, we need the interface to be twice as fast as PCI-e 2.0 for RAID purposes.
Second, we need to have HDDs and SSDs that perform above the SATA 2.0 mark (375 MB/s Max Throughput).
I can wait for the next generation of chipsets (which will possibily have the PCI-E 3.0).
I am a AMD fanboy and have used only AMD cpu's for 10 years and when i built computers for friends i only use AMD! So it seams that infell is not as good as they say.
This is why I bought 1366 over 1156!
The LGA1156 technology was dead when it arrived. The only thing it has is the removal of the northbridge. I won't and would never buy the 1156-series. It was retarded that they just didn't make them all LGA1366. But that is marketing for ya.
I am not an AMD fanboy and have never used an AMD processor, but I too have to agree with SpadeM and others that there should have been an AMD board thrown in the mix for comparison. Yes the article is "USB 3.0, SATA 6Gb/s, Motherboards, And Overcoming Bottlenecks", and that is EXACTLY why it should have compared these various "solutions" with a bottleneck free AMD set-up. Just how do the suggested solutions compare with a bottleneck free MB??? Are they adequate and cost effective solutions in comparison?
That is the real question that needs to be answered because when I go to buy my next set-up, I would like to know if it's worth sticking with Intel P55, or upgrading to Intel X58, or switching to AMD. A true comparison covering this is in order.
Totally agree with niknikktm +1
This makes for an interesting tradeoff if someone doing a build now. There not a lot of USB/SATA 3.0 peripherals out there yet. The Intel CPUs are plainly better, but they have this IO bottleneck that will be a future issue.
Are the next gen AMD CPU's (Bulldozer, Et Al) going to be backwardly compatible with the current gen Mobos (meaning with the use AM3.) I could see buying a current gen AMD CPU/Mobo, if I can just swap out the CPU later when they catch up to Intel. But if I have to swap out the mobo also, what am I gaining now, when I can't really buy anything to plug into the higher speed ports?
Unless they use raid 0 ssd's a amd vs intel comparison isn't in order.Because a single drive would show no difference,it only shows up on some of the intel boards when you run 2 video cards.......as they have clearly shown in the article.