AMD's 890GX Chipset - Same Graphics, Better South Bridge
by Anand Lal Shimpi on March 2, 2010 4:36 AM EST- Posted in
- CPUs
Testing the SB850’s SATA Controller
Update: New 3Gbps and 6Gbps results on the AMD 890GX here.
In my review of OCZ’s Vertex Limited Edition SSD I previewed some of the results of the world’s first SSD with native SATA 6Gbps support - Crucial’s RealSSD C300. Capable of sequential read speeds greater than 333MB/s, the C300 is the only drive in the world that can actually benefit from 6Gbps SATA at this point.
There’s just one problem. My RealSSD C300 died in the process of testing it with the 890GX. I don’t believe it was the motherboard or chipset, but right now it looks like I stumbled upon an untested usage case that put the drive in a state where it won’t even let a system POST anymore.
It’s because of situations like this that I’ve been very cautious in recommending any new SSDs. Hence my conclusion in the Vertex LE review:
“Go up another $100 and the recommendation is easily the Crucial RealSSD C300. Again, assuming that nothing horrible ever happens with the drive. I do have more faith in Crucial’s validation testing given that Micron is shipping the same drive to OEMs, but it’s still a brand new, unproven platform.”
With the bricked C300, I can’t provide any 6Gbps results on the 890GX unfortunately. I should have a new drive in about 12 hours so I’ll update here once I do get it. With the C300 out of my parts bin, I switched to a drive that could really push the limits of 3Gbps SATA - the OCZ Vertex LE.
Unfortunately, in doing so I uncovered another problem - this time with the 890GX. It’s AHCI performance is noticeably lower than Intel’s:
| 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 |
| AMD 790GX | 247.8 MB/s | 213 MB/s | 37.6 MB/s | 119.5 MB/s |
| Intel H55 | 264.9 MB/s | 247.7 MB/s | 48.6 MB/s | 180 MB/s |
AMD’s south bridge ends up delivering anywhere from 72 - 93% of the performance of Intel’s ICH. While this isn’t something that you’d necessarily see with hard drives, it is something that is evident with SSDs since they do actually push the limits of 3Gbps SATA. To make sure it wasn’t an iometer thing I also copied a 2.4GB x264 over from the boot drive (Intel X25-M G2 160GB) and still noted slower performance on AMD’s chipset. This is actually an improvement over the SB750 used in the 790GX/FX. Performance was even worse back then, particularly with writes.
And in case you’re wondering, running the SSD in Native IDE mode didn’t help either - performance was expectedly slower.
ASUS’ engineers apparently ran across something similar. They found that disabling C1E and Cool’n’Quiet boosted drive performance and recommended I try it. The results were unexpectedly higher, but not on par with Intel’s ICH performance:
| 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 |
| AMD 890GX (C1E/CnQ Disabled) | 256.4 MB/s | 234.8 MB/s | 42.3 MB/s | 135.3 MB/s |
| Intel H55 | 264.9 MB/s | 247.7 MB/s | 48.6 MB/s | 180 MB/s |
Obviously disabling important power management features isn’t a long term solution, but it does show that AMD may be able to provide a future hardware or BIOS fix for the problem.
Slower SSDs didn’t exhibit the problem. I tried the Indilinx Barefoot based Mushkin Io:
| Iometer 6-22-2008 Performance | 2MB Sequential Read | 2MB Sequential Write | 4KB Random Read | 4KB Random Write (4K Aligned) |
| AMD 890GX | 229.6 MB/s | 166.5 MB/s | 35.7 MB/s | 13.4 MB/s |
| AMD 790GX | 229.7 MB/s | 166.5 MB/s | 35.7 MB/s | 13.4 MB/s |
| Intel H55 | 236.9 MB/s | 164.4 MB/s | 36.0 MB/s | 13.4 MB/s |
It appears that the dropoff only happens in one of two cases: 1) When you’re pushing a lot of IOPS (e.g. 4KB random write tests on the OCZ Vertex LE) or 2) When you’re pushing a lot of bandwidth (e.g. 2MB sequential read tests on the OCZ Vertex LE).
As a mainstream chipset, the SATA issues don’t really matter. Unfortunately, if you are going to buy a high performance SSD then it may be an issue.
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semo - Tuesday, March 2, 2010 - link
Hi Anand,I noticed something strange with my Sharkoon ( http://www.sharkoon.com/html/produkte/docking_stat...">http://www.sharkoon.com/html/produkte/d...tations/... )device recently and I thought you might find it interesting. I had a 3.5" SATA drive connected to it and I just switched off my PC. When it turned off, the case fans kept spinning (CPU fan spinning up/down constantly) and the card reader/temp sensor turned red and started beeping. It kept doing after I took off the power cord. After 10 mins of looking around and head scratching I remembered that the Sharkoon has power going to it. Unplugged that and the PC shut down. I don’t think I’ve seen this anywhere else but the Sharkoon’s USB power is actually bidirectional (the DriveLink at least). That doesn’t happen usually I think and maybe different motherboards won’t like this.
That’s unfortunate that your C300 died. I wonder why if a non essential device like drive fails, the system doesn’t POST. There shouldn’t be such a condition ever (I actually have one SATA drive that does that actually). Something as simple as removing the DVD drive belt can cause the system to POST or at least take much longer to do so. Why, the thing is not essential?
Also do you have an explanation why the Vertex LE has such good write performance compared to read. I’ve assumed that you expect the opposite from NAND flash.
Looking to full review of the 890FX, hopefully it will be more polished!
SunLord - Tuesday, March 2, 2010 - link
that has to be a defect... There is no way anyone would design something to send power into a computer via a usb port it would cause all kinda of bad voodoo for the systemSunLord - Tuesday, March 2, 2010 - link
Why does the index indicates that the 890GX is DirectX 10.1 and has UVD2 while the 790GX is DX10 and UVD1 if they are exactly the same? Is the index wrong or do these changes require no hardware tweaks?Anand Lal Shimpi - Tuesday, March 2, 2010 - link
I've updated the article a bit. The move from DX10 to 10.1 in AMD's case didn't require much of a change. Technically the 890GX is more like a 785G/790GX hybrid. Either way, performance is identical between all of the cores clocked at 700MHz.Take care,
Anand
SunLord - Wednesday, March 3, 2010 - link
Put some active cooling on it and overclock it!psychobriggsy - Tuesday, March 2, 2010 - link
At least the southbridge is better featured, with SATA3 and GigE, even if the former wasn't really tested in this review, and the latter wasn't utilised.Shame that AMD didn't bump the shader count to (e.g.,) 60, it would have made a massive difference since Intel actually put some effort in on their recent attempts. Then again, Cedar 5450 should have had 160 shaders in my opinion to make it a reasonable low-end purchase.
Clearly it's a tide-over chipset until Llano changes everything.
nice123 - Tuesday, March 2, 2010 - link
They can't boost it to 60 sadly because they are arranged in blocks of 40 - the next step up is 80, which is of course Radeon 5450 territory since they decided not to add any more shaders to that and kept it exactly the same performance as the 4550.fiki959 - Tuesday, March 2, 2010 - link
I am little disappointed with the new chipset. But there is a reason that AMD didn't improve IGP performance because doing so will probably hurt radeon 5450 sales. An improvement of 30-50% will bring the IGP very close to low end dedicated cards so maybe that is the main reason or staying with 55nm process have something to with the decision I don't know..By the way I see some Athlon 2 laptops in my country, some review for these CPUs please.
shrihara - Tuesday, March 2, 2010 - link
If it has USB 3.0 which is backward compatible, then what is the need of having USB 2.0 along with that? I was hoping that AMD 890 will come up with only USB 3.0 on board like SATA 6GBps.strikeback03 - Tuesday, March 2, 2010 - link
because for whatever reason AMD didn't include USB3 and they didn't want to spend the money/PCIe lanes on a bunch of external USB3 controllers?