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AMD has definitely caught my interest with the steps they've taken towards embracing open-source software recently. I run Linux full time, and the open source m

AMD has definitely caught my interest with the steps they've taken towards embracing open-source software recently. I run Linux full time, and the open source movement is really important to me, but I went with Intel and Nvidia when I built my new computer last year. My last rig was all AMD, and while it was really powerful for the time it was built, it was basically a space-heater. The power supply on my current machine wouldn't even run my old computer at idle. I have a philosophical issue with the way that Nvidia and Intel handle their Linux drivers and interact with the open-source community, but after 7 years with a computer that sounded like a jet engine, I just wanted silence. I know it seems disingenuous to compare a 7 year old computer to a modern one, but the TDP of AMD products has not improved much during that time. Plus, my computer spends most of it's time near-idle, and Intel and Nvidia look better the lower the utilization. The fans in my new rig don't even spin up unless I'm doing something rather resource intensive, like playing game. So, despite my misgivings about Intel, there was no chance I was going to with AMD. The Bulldozer architecture is terrible. Bulldozer hasterrible performance, regardless of whether you measured actual performance, or performance per watt. The only reason I considered AMD was because they enable virtualization on all of their processors (or at least the ones I was considering), whereas Intel only allows virtualization on Xeon and K-series processors. My biggest issue right now is that Nvidia takes steps to prevent their non-Quadro cards from working in VFIO passthrough. I could have just as easily gone AMD, which I understand works much better with VFIO; the main reason I went with Nvidia for graphics was because I got the 970 for a song. Plus, after years of using AMD with Linux, I don't really trust AMD drivers to work. Nvidia drivers might be closed-source, but they work as long I wait a week to upgrade after a new driver is released. The Zen architecture seems like it will hit all the right notes for me, as long as AMD maintains their welcoming approach to virtualization.

mattst88 10y ago
> whereas Intel only allows virtualization on Xeon and K-series processors. I'm not an expert on Intel CPU market segmentation, but I do work for Intel on the i965 Mesa driver. I don't think your statement is true. See http://ark.intel.com/search/advanced?s=t&VTX=true http://ark.intel.com/search/advanced?s=t&VTX=true That's a list of all Intel CPUs with VT-x. It's really easy to narrow down the selection from there. FWIW, I see lots of Skylake i3, i5, and i7s with VT-x.
- justabystander 10y ago
  He probably means VT-d since he mentioned passthrough. VT-x is just the virtualization extensions needed for many hypervisors, while VT-d lets your VMs directly access the actual physical hardware. Like dedicating a physical GPU or NIC to a VM. I'm not sure which modern CPUs and motherboards support that. I know back in the Core2 days when VT-d was first introduced, it was a nightmare to find the right combination. Looking from the outside, Intel also seems to play a lot of marketing games with their CPU features. Sometimes top-of-the-line CPUs will be missing features that others have. Like selling a $6K Xeon CPU manufactured this quarter without virtualization support. (http://ark.intel.com/products/95831/Intel-Xeon-Phi-Processor-7290F-16GB-1_50-GHz-72-core http://ark.intel.com/products/95831/Intel-Xeon-Phi-Processor...) Supposedly they want to get that feature in there at a later date, but that's not something we like to trust in with computer components. Your VT-x search returns 1459 products, while the VT-d search returned only 788. Here's a list of things that say they support VT-x but not VT-d (http://ark.intel.com/search/advanced?s=t&VTX=true&VTD=false http://ark.intel.com/search/advanced?s=t&VTX=true&VTD=false). Pretty sure some entries on it are wrong, but Intel is also terrible about keeping old technology names on newer spec sheets. Maybe they folded VT-d into VT-x without telling the world?
  - mattst88 10y ago
    FWIW, it appears that all of the i3, i5, and i7 Skylakes support both VT-x and VT-d. I agree that this has been confusing in the past (as evidenced by the mix of Atom, Celeron, Pentium, i3, i5, i7, Xeon in your link), but I think at least in VT-* it's been greatly simplified.
    - Declanomous 10y ago
      I thought I was going crazy, because I thought only the newest Haswell K-series processors supported VT-d, but I found this link which indicates it is available on basically everything now: http://www.tomshardware.com/answers/id-2031324/4770k-virtualization-support.html http://www.tomshardware.com/answers/id-2031324/4770k-virtual... From April 2014: Craziest thing. The i7-4770K NOW does support vt-d. It didn't used to, but went on their site today.... I checked the edit history for the Haswell architecture on Wikipedia, and it appears that VT-d was supported by all i5s and i7s, except the K series, save for the 4790k and it's i5 counterpart since at least August of 2014. I'm not sure where I got the idea is was more limited. I had been speccing a computer for a couple of years at that point, so I wouldn't be surprised if I'm digging up irrelevant information.

mattst88 10y ago

> whereas Intel only allows virtualization on Xeon and K-series processors. I'm not an expert on Intel CPU market segmentation, but I do work for Intel on the i965 Mesa driver. I don't think your statement is true. See http://ark.intel.com/search/advanced?s=t&VTX=true http://ark.intel.com/search/advanced?s=t&VTX=true That's a list of all Intel CPUs with VT-x. It's really easy to narrow down the selection from there. FWIW, I see lots of Skylake i3, i5, and i7s with VT-x.

justabystander 10y ago
He probably means VT-d since he mentioned passthrough. VT-x is just the virtualization extensions needed for many hypervisors, while VT-d lets your VMs directly access the actual physical hardware. Like dedicating a physical GPU or NIC to a VM. I'm not sure which modern CPUs and motherboards support that. I know back in the Core2 days when VT-d was first introduced, it was a nightmare to find the right combination. Looking from the outside, Intel also seems to play a lot of marketing games with their CPU features. Sometimes top-of-the-line CPUs will be missing features that others have. Like selling a $6K Xeon CPU manufactured this quarter without virtualization support. (http://ark.intel.com/products/95831/Intel-Xeon-Phi-Processor-7290F-16GB-1_50-GHz-72-core http://ark.intel.com/products/95831/Intel-Xeon-Phi-Processor...) Supposedly they want to get that feature in there at a later date, but that's not something we like to trust in with computer components. Your VT-x search returns 1459 products, while the VT-d search returned only 788. Here's a list of things that say they support VT-x but not VT-d (http://ark.intel.com/search/advanced?s=t&VTX=true&VTD=false http://ark.intel.com/search/advanced?s=t&VTX=true&VTD=false). Pretty sure some entries on it are wrong, but Intel is also terrible about keeping old technology names on newer spec sheets. Maybe they folded VT-d into VT-x without telling the world?
- mattst88 10y ago
  FWIW, it appears that all of the i3, i5, and i7 Skylakes support both VT-x and VT-d. I agree that this has been confusing in the past (as evidenced by the mix of Atom, Celeron, Pentium, i3, i5, i7, Xeon in your link), but I think at least in VT-* it's been greatly simplified.
  - Declanomous 10y ago
    I thought I was going crazy, because I thought only the newest Haswell K-series processors supported VT-d, but I found this link which indicates it is available on basically everything now: http://www.tomshardware.com/answers/id-2031324/4770k-virtualization-support.html http://www.tomshardware.com/answers/id-2031324/4770k-virtual... From April 2014: Craziest thing. The i7-4770K NOW does support vt-d. It didn't used to, but went on their site today.... I checked the edit history for the Haswell architecture on Wikipedia, and it appears that VT-d was supported by all i5s and i7s, except the K series, save for the 4790k and it's i5 counterpart since at least August of 2014. I'm not sure where I got the idea is was more limited. I had been speccing a computer for a couple of years at that point, so I wouldn't be surprised if I'm digging up irrelevant information.