Earlier this month my Crucial RealSSD C300 died in the middle of testing for AMD’s 890GX launch. This was a problem for two reasons:

1) Crucial’s RealSSD C300 is currently shipping and selling to paying customers. The 256GB drive costs $799.
2) AMD’s 890GX is the first chipset to natively support 6Gbps SATA. The C300 is the first SSD to natively support the standard as well. Butter, meet toast.

Since then, Crucial dispatched a new drive and discovered what happened to my first drive (more on this in a separate update). While waiting for the autopsy report, I decided to look at 890GX 6Gbps performance since it was absent from my original review.

AMD's SB850 with Native 6Gbps SATA

In the 890GX review I found that AMD’s new South Bridge, the SB850, wasn’t quite as fast as Intel’s ICH/PCH when dealing with the latest crop of high performance SSDs. My concerns were particularly about high bandwidth or high IOPS situations, admittedly things that you only bump into if you’re spending a good amount of money on an SSD. Case in point, here is OCZ’s Vertex LE running on an AMD 890GX compared to an Intel X58:

Iometer 6-22-2008 Performance 2MB Sequential Read 2MB Sequential Write 4KB Random Read 4KB Random Write (4K Aligned)
AMD 890GX 248 MB/s 217.5 MB/s 38.4 MB/s 130.1 MB/s
Intel H55 264.9 MB/s 247.7 MB/s 48.6 MB/s 180 MB/s


My concern was that if 3Gbps SSDs were underperfoming on the SB850, then 6Gbps SSDs definitely would.

Other reviewers had mixed results with the SB850. Some boards did well while others did worse. I also discovered that AMD’s own internal testing is done on an internal reference board with both Cool’n’Quiet and SB power management disabled, which is why disabling CnQ improved performance in my results. As far as why AMD does any of its own internal testing in such a way, your guess is as good as mine.

I received an ASUS 890GX board for this followup and updated to the latest BIOS on that board. That didn’t fix my performance problems. Using AMD’s latest SB850 AHCI drivers however (, did...sort of:

Iometer 6-22-2008 Performance 2MB Sequential Read 2MB Sequential Write 4KB Random Read 4KB Random Write (4K Aligned)
AMD 890GX (3/2/10) 248 MB/s 217.5 MB/s 38.4 MB/s 130.1 MB/s
AMD 890GX (3/25/10) 253.5 MB/s 223.8 MB/s 51.2 MB/s 152.1 MB/s
Intel H55 264.9 MB/s 247.7 MB/s 48.6 MB/s 180 MB/s


All performance improved, but we’re still looking at lower performance compared to Intel’s 3Gbps SATA controller except for random read speed. Random read speed is faster on the 890GX (but slower than X58).

The best part of it all is that I no longer had to disable CnQ or C1E to get this performance. I will note that my performance is still lower than what AMD is getting on its internal reference board and the performance from 3rd party boards varies significantly from one board to the next depending on board and BIOS revisions. But at least we’re getting somewhere.

In testing the 890GX, I decided to look into how Intel’s chipsets perform with this new wave of high performance SSDs. It’s not as straightforward as you’d think.

The Primer: PCI Express 1.0 vs. 2.0
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  • sparkuss - Thursday, March 25, 2010 - link


    I was going to maybe get two C300's for my current build. Do we consumers need to wait for your update before we invest in these?

    We know it died, but I haven't been able to find any other reliability statistics collated anywhere to make a buying decision on.
  • sparkuss - Thursday, March 25, 2010 - link

    Sorry, I missed the Update link in the upper corner.
  • vol7ron - Thursday, March 25, 2010 - link

    Great review. Not much to be said. There was a little bit of puffery at the end, in AMDs favor.

    I'm sure most companies have faster controllers/BIOSs to be released. Rather than saying AMD is something to look out for, for some reason I'd think Intel would have something greater.

    As you mentioned, the on-die controller should have lower latencies - could you ask them about this? Perhaps some of the PCI bandwidth is being chewed up by something else, or perhaps the latencies are too low, causing a check/repeat bottleneck? (or maybe this a marketing ploy to release something faster in the future)
  • Dzban - Thursday, March 25, 2010 - link

    Because AMD has native 6Gbps and they are improving drivers. With intel chipsets you can't phisicly increase speed further.
  • vol7ron - Thursday, March 25, 2010 - link

    I don't like how Intel switches between [Mb/s & Gb/s] and [MB/s & GB/s]. It'd be nicer to not have to translate 480Mbps into 60MB.

    I guess the issue was at first past I almost equated the 480Mb/s to the 500MB/s right under it.
  • jejeahdh - Thursday, March 25, 2010 - link

    You should not type dates in that format, and if you had an editor, he or she should absolutely stop you from doing such things. People have expectations. You might think it's no worse than the ever-present traditional ambiguous formats of the US and Europe (m/d/yy(yy), d/m/yy(yy)) which are bad enough, but at least it's an old and well recognized problem that people are used to living with, so long as it uses slashes. People with knowledge of standards, though, use dashes for ISO date format, yyyy-mm-dd which is also perfectly sortable. By mixing and matching styles haphazardly, you're only propagating the notion that anything goes, causing people to stop and wonder for 12 days out of every month. If you're deliberately adopting the style commonly used in the Netherlands (I had to look it up) and advocating its use for an international audience, I cannot imagine why.

    I know it seems crazy to harp on this and I kind of agree . . . but I am just so surprised to see it here, written by a detail oriented technically minded accomplished writer.
  • strikeback03 - Friday, March 26, 2010 - link

    If this is in response to the IOMeter build, that might be the way it was named by its creator, not Anand. Also, I would imagine 6-22-2008 is m-dd-yyyy
  • assassin37 - Thursday, March 25, 2010 - link

    Hey Anand, Why isn't the X-58 gigabyte native 6gbs board on the write benchmarks?
  • assassin37 - Thursday, March 25, 2010 - link

    never mind I read why, legacy mode
  • vailr - Thursday, March 25, 2010 - link

    Intel releases SSD friendly AHCI/RAID driver:

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