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USB 3.0 the Real Deal, SATA 6GB Not Yet
MojoKid writes "HotHardware has posted a sneak peek at a new motherboard Asus has coming down the pipe with USB 3.0 and SATA 6G support. The Asus P7P55D-E Premium has a PLX PCI Express Gen 2 switch implementation that connects to NEC USB 3.0 and Marvell SATA 6G controller chips. With a USB 3.0 enabled external hard drive connected to a USB 2.0 port and then to the board's USB 3.0 port, there were some rather impressive gains to observe. When connected to a USB 3.0 port, the external hard drive was about 5 — 6x faster versus connecting over USB 2.0, with total throughput in excess of 130MB/sec. On the other hand, benchmarks with Seagate's new Barracuda XT SATA 6G drive show little performance difference but a burst rate that is off the charts. According to ATTO, there are slight overall performance benefits to be had connecting the drive to the SATA 6G controller, but the deltas were quite small; somewhere in the neighborhood of 5MB/s or so."
The Barracuda XT is a spinning platter HDD and so should not be expected to benefit significantly from the new SATA revision. SSDs on the other hand have already maxed out the transfer rate SATA 3Gbps. I suspect they would have seen the difference if they used a top of the line SSD.
This is good news all around, it's great to see things getting faster.
Make the chart bigger!
This all sounds like exactly what you'd expect.
The old SATA standard was more than sufficient for the hard disk's max sustained transfer rate, so only burst performance (when everything is presumably coming from the disk's RAM cache) changed with the new SATA. So "SATA 6GB" is working fine, but this disk is just too slow to take advantage of its speed increase.
With USB on the other hand, USB 2 is simply far too slow to handle even the drive's sustained transfer rate, whereas USB 3 is fast enough to handle it.
So the moral seems to be: USB 2 sucks for disks, USB 3 is better and probably sufficient for a typical hard drive, and SATA's still probably better than either (it's not really possible to tell from this article, since the sustained transfer rates are limited by the drive, and they curiously omitted the burst rates for USB).
We live, as we dream -- alone....
SATA 2 is already a bottleneck for many SSDs as this chart shows them hitting a wall at approximately 260MB/s. SATA 3 should release the proverbial floodgates for sequential reads.
On a tangent, Samsung just started mass production of a 64MB, 60nm phase-change RAM in September. Initially they are going to use them in mobile phones. The chips read, write and erase approximately 7 times faster than Flash memory, and also use less power. Sooner rather than later Samsung or the other PRAM producer Numonyx will put the chips in SSDs that can read and write at around 1GB per second.
From what I can see in the graphs the USB3 HDD is indeed faster than on USB2 because of the bandwith; the SATA HDD is about the same on SATA 2 and 3, but also pretty near USB3. The title is implying superiority of USB over SATA when clearly the HDD is the limiting factor.
What, USB 1 slow? Seems like you never tried to transfer 3GB of photo's to a PC that only has a keyboard to type them pixel by pixel.. Seriously, USB 1 is FAST. If you want slow, try typing down 3GB.
It's faster. In their tests, they were getting 140MB/s transfers through USB3 to a single drive. I have two (older, slower) drives that can, between them, saturate a FireWire 800 bus giving me a total throughput of a shade under 100MB/s. One thing the tests didn't show was how well USB3 scales. What happens when you plug two disks in to a single USB3 port? What about four or five? I can chain together FireWire 800 disks and see it scale almost linearly, but can I do the same with USB3 hubs? In real-world usage, USB2 was much slower than FireWire 400 due to protocol overhead. Has this been improved with USB3? What happens if I run a USB1 keyboard on the same hub as my USB3 disk? The FireWire standard goes up to 3200Mb/s, although I've never seen an implementation that goes over 800. USB3, apparently, gives the same speed after protocol overhead, but how close to this can it get in the real world? USB 2 had a very high CPU load compared to FireWire, has this been fixed with USB3?
It seems that USB3 has fixed most of the things that made FireWire better than USB2, and FireWire 3200 isn't supported anywhere that I've seen, so USB3 probably has more long term future. It's not clear that USB3 is better than FireWire 3200, but it does have one big advantage: it's actually being deployed. It is clearly superior to FireWire 800, which is the fastest FireWire you'll find on existing systems.
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The big question with USB 3.0 is the price. That is the big advantage of USB over competitors like FireWire. Cables, host controllers, devices, hubs, everything is cheap. USB 3.0 looks a lot more complicated. The cables are much thicker with more wires and shielding. A USB 3.0 hub has to contain everything a USB 2.0 hub does, plus the new SuperSpeed part which is no longer just a dumb hub but more like a switch or router.
You're spot on with the CPU load. The reason Firewire is still so popular, and the reason why Mac users were so up in arms when Apple dropped it from their alu MacBook is that for video and audio there's still no good alternative. I can hang 16 channels of digital audio I/O from the Firewire bus and do live digital mixing on a Mac and run digital effects etc.. There's no way I could do that with USB and expect it to be stable if it works at all. Jobs made a big thing about newer digital video cameras being USB2, but the point is it's offline in the sense that you're transferring data from one hard drive in the camera to a hard drive in the computer - if there's a problem with the USB2 bus the camera can throttle back the data transfer or repeat if necessary. If you're using a tape-based digital format (which is still the mainstream standard in the pro/semi-pro world) then you need Firewire because it will reliably import a full tape without dropping frames; effectively it's streaming rather than just copying, for which I wouldn't trust USB2.
I don't know why the editors didn't include a link to it, but AnandTech has a much better review of the SATA 6G-equipped motherboard and its performance; one that actually gets around to doing real-world tests and not just synthetic tests. It turns out that the 6G Marvell controller is slower than the standard Intel ICH10 controller in virtually all cases. Until someone integrates SATA 6G in to a proper motherboard chipset, it's not just performance limited, it's performance degrading.
I like FireWire, but I think at this point it's dead. I have a couple of external FireWire 800 disks, but every other peripheral that I own is now USB. With USB 3, FireWire 800 is now much slower, so if I buy another disk it will be USB 3, not FireWire 800. The next laptop that I buy will have several USB 3 ports and I will be able to plug anything into them, from mice up to disk arrays. FireWire 3200 has been promised for years, but still isn't shipping, while USB 3 and eSATA both are. eSATA is a better choice if you just want disks, USB 3 is a better choice if you want flexibility (there are a lot more USB devices than FireWire devices, and FireWire 400, 800, and 3200 all have different connectors).
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Intel were very clever pitching USB as a replacement for things like PS/2 and RS-232 connectors. That meant that everyone had a USB port or two and collected USB 1 devices. When USB 2 came around, even though it wasn't quite as good as FireWire 400, it was almost as good and it was effectively free, because there was almost no price difference between a USB 1 and a USB 2 controller, and you needed a USB 1 controller for everyone's keyboard and mouse. Now USB 3 is here, the same is going to happen. USB 2 controllers will be replaced by USB 3 controllers, and everyone will have a set of USB 3 ports. FireWire doesn't just have to be better, it has to be better by enough of a margin to make it worth adding an extra controller, extra motherboard traces, and extra ports.
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