This question would best be addressed to Wendell, as he is the only person that i know owns both cpu's, however i dont dare ask a hardware question in inbox.exe.
Im building a home VM server soon, either running either esxi, xen, or proxmox. I am attracted to the new 8 core atom boards, but dont want to be limited on power, so i am also considering an underclocked fx-8350. the question is, to anyone who has experience with both systems, will i feel limited by cpu power on the Atom C2758, and if so will it be enough to justify going with the 8350 at 5x the TDP?
maybe not exactly what you looking for, but I am using a 55W TDP i3 3250 for OS Win 2012 Server, with pfsense and xpenology both in Hyper V. CPU is plenty fine, using 16GB RAM, wifi for pfsense, intel quad nic. g/l
I can't speak for the Atom board but I've got an FX 6300 running Proxmox on an el cheapo mATX board and it works great. Do invest in an aftermarket heatsink though... The stock AMD one is so bad if you put it over an ice cube it would probably make it melt. The CPU is great but the cooler might as well be fire in a box.
I guess the question should be what are you trying to run on this virtual server? That little avaton board could handle some small vms, but depends on what they are.
The atom board would do great with containers, but based on my experiences with KVM it would crawl with KVM VMs. A low clockspeed chip like that generally seems to give lower performance than a higher clockspeed chip with less cores. That's just my experience but personally I'd get an 6300 and a Gigabyte GA-78LMT-USB3 board and 16GB of ram and a couple WD 2TH Red drives
I personally own a Avoton Super micro board and in a few words its absolutely amazing. It almost as fast as a v3 Xeon and it has more cores to work with for virtualization. It was quite pricey, but for the level of performance you get in such a tiny powered envelope its well worth it. Its nice having 8 physical 2.5ghz cores to play with rather then 4 with hyper threading. Don't let hyper threading fool you, in some cases it can actually slow down virtualization rather then speeding it up.
Wait, the avotons are 2.5ghz? I thought they were 1.5ghz...on second thought if that's the case the avoton board might be perfect for this...I just know KVM seems to do better for me on higher clockspeed CPUs so if its 1.5 it may be sluggish but if its 2.5 and you have the money I'd go for it.
Yessir, sorry its 2.4Ghz X 8 cores with AES acceleration. At one point I had everything on my network virtualized on it using proxmox....(pfsense, windows server 2008R2, web server, etc.) The supermicro board I have has quad intel nics :) and I believe I was only drawing around 50-60 watts from the wall. Built it in one of these sexy little beasts.
Again I will reiterate. It depends on the virtualization work you are doing.
The avaton does not support vt-d, only vt-x, meaning simply that you will be unable to do a pci device pass-through to a guest OS. If you wanted to do any gpu work, or maybe a pass-through to a raid controller (why I dunno, but just throwing that out there) this could be a large problem.
Now, if you don't need that feature, yes, it could do some small virtual guests, but again, it depends on what you are doing on those guests. Realize that multi-core benchmarks place this cpu around the area of an i3 4130.
Let's say you want one virtual for, say, a small *nix minecraft server, and another to serve as a *nix nas, and another to test out the new windon't (pun intended) 10, or possibly what psigus did above, It would be able to do this relatively well.
However, for testing larger virtualization deployments, I suggest you look elsewhere.
It just depends on how big of a virtualized environment you want, and what features you are looking for. You can't simply place a blanket on a chip saying it's "good" or "bad". It always depends on the workload.