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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Taft12 - Tuesday, March 2, 2010 - link
Fully agreed here, the lack of chipset competition has led to stagnation on both the AMD and Intel sides of the fence.Especially Intel, Anand admitted in the H55 coverage that Intel did not reduce chipset pricing even though removal of the IGP reduced their costs significantly. This horseshit would not occur if Nvidia and others weren't being blocked from creating their own offerings.
Penti - Tuesday, March 2, 2010 - link
They don't have licenses to produce chipsets any more. I fully disagree that it has led to stagnation though. Removing the memory controller on AMDs didn't lower the cost either. Both AMD and Intel finally has some enterprise (business) features such DASH and vpro too. Others simply couldn't keep up, nVidia killed ULI when they bought them, SiS and VIA has dropped out since a long time ago. Gaming components like nVidia 980a won't do a dent regardless of price.MadMan007 - Tuesday, March 2, 2010 - link
Hey Anand, thanks for including a modern low-end card for reference. I do have a request for what might be a useful article wrt IGPs for you. I'd like to know not how poor IGPs are compared to modern cards but rather to which *older* graphics card they are equivalent. Personally I haven't gotten many new games in a while and with Steam sales have been picking up some older ones too, there may be others in the same boat. Now when a game says it requires a much older card like a GF3 or Radeon 9000 or what have you I am pretty sure a modern IGP is better but once things start getting in to DX9 cards I'm not so sure. Would an IGP be equivalent to a 6600GT, or a Radeon 850?If you were to have someone do an article looking at this with older games that would be awesome and a great service to those who just play older games at this point. Finding IGP performance on older games is not easy.
nice123 - Tuesday, March 2, 2010 - link
Remember, GlobalFoundries is new. AMD are still using TSMC's 55nm process for this chipset. This is most probably because their 40nm process is absolutely crap. (as seen with the Radeon 5xxx yields and lack of Fermi)When AMD move to GlobalFoundries I think their hardware will pick up more, we won't have TSMC screwing up every single process they do.
Penti - Tuesday, March 2, 2010 - link
Still? What are you talking about, practically nobody uses the latest node for chipsets and many other none bleeding edge speed ASICs. At least they moved from 65nm. Intel chipsets are manufactured at 65nm.They won't move to GlobalFoundries for fabbing chipset/GPU logic till Liano APUs I guess they will design chipsets for GF then too.
Foxi - Tuesday, March 2, 2010 - link
AMD should ban Anand from testing theirs stuffs. It's a shame and pathetic as well. :sstrikeback03 - Tuesday, March 2, 2010 - link
lol, which part of this article offended you, fanboi?Penti - Tuesday, March 2, 2010 - link
How about the IOMMU (AMD-Vi) support in the SB850 chipset? It's supported right? I want to know if the chipset and bios combo has it working.semo - Tuesday, March 2, 2010 - link
Wondering about that too. I've seen articles here test for virtualization performance but only in the server space. Would be good to see more info about these sort of things around herePenti - Tuesday, March 2, 2010 - link
Yeah it works for SR5650-70-90/SP5100 server chipset, but it's not identical even if it's the chip it's based of. So I was wondering if there's really support in the silicon and perhaps more important if it's supported in the BIOS. Otherwise it's not really interesting for me. I will still only consider the Opteron platform for an AMD machine then and it makes choosing a Intel machine so much easier. But I guess not since AMD don't mention it. Might not matter for desktops, but it do for workstations and Intel desktops supports it (IOMMU). AMD-V is of course there but that's a whole other matter.