I guess since it is a production machine you don't have the time to see how well it can undervolt?
Oh, I suppose once the workload eases off a bit (we're in a crunch time right now) I might have some time to play around with it a bit. Not much motivation to undervolt though since the fan only becomes audible when I really push it, and I'm not paying for the electricity.
Personally I went ahead and bit the bullet on a dual Operton 4284 setup (Bulldozer). To tell you the truth BD's performance is remarkably better in Linux than it is in Windows. Handbrake itself is easily 25 to 30% quicker in Linux and everything just feels snappier. To me at this point BD's are actually a pretty good deal.... IF you are honest with yourself on why you are buying it. I primarily run Linux where BD runs better. I also run VM's normally day to day and I play the random Linux game or two.
Yes, I run VMs as well, both to build (other) projects that need specific build environments, and to run the obligatory Windows VM to deal with the corporate stuff. Since it's a work machine I'm not gaming though...
For me it performs quite well. I've run a game while having my normal 2 VM's up and didn't even notice they were running. This wasn't possible on my i7 workstation before. Overall I like the performance of it considering the price I paid for the whole system which was 900 for procs+MB and another 200 for the memory.
Yup, like I said bang for the buck seems to be pretty good. My office mate upgraded just a couple of weeks before me, but went Intel instead. I think he spent nearly twice as much (of someone else's money...
) for roughly equivalent performance, and doesn't have support for ECC RAM (yeah we can argue about how important that is on a desktop) or IOMMU (which could come in handy given the sort of things we do... being able to hand off bare PCI/PCIe devices to a VM could come in handy).
Regarding Turbo and C6 states.. I have noticed the peculiar behavior as well. It seemed to idle at 1400 and clock up to stock @ 3000Mhz. However, I was using system-monitor and some widget to view my clock speed... these didn't report it right. I had to use cpufreq-aperf to physically see it break past the stock clock.
Sounds like a slightly different (but possibly related) issue. It seemed to behave more or less as you describe when CnQ was enabled. But with CnQ disabled (how I'm running it now) it appears to be running 300MHz *above* stock even when it is idling. At least, that's what /proc/cpuinfo is telling me... it could be lying to me, especially given that I'm still running Ubuntu 10.04 LTS (which predates the Bulldozer core).
The years just pass like trains. I wave, but they don't slow down.
-- Steven Wilson