First, please let me say Hello!

Now a days I build up a new workstation based on Haswell EP.

Cause I gained some experience over the last years, again I setup XenServer 6.5 and 7.0.

Unfortunately with new hardware platform the issues were not less - the opposite was in my case...

 

My current hardware setup is a Z10PE board with two E5-2686 cpu's.

I come from sandybridge with 2x7970 GPU's and after a lot of pain I got it running on XenServer6.x.

Also 2xCrossfire was working for some benchmarks but it was not relevant for my GPGPU tasks, so I never followed the path...

But today I with my new workstation build I want to get the flexibility with having multiple GPU's for dedicated desktops - but why not crossfire then for gaming in ultra settings if they are available?The new workstation has

So again I started with XenServer 6.5 cause I know it so its my baseline for a working system.

The new workstation has this hardware secs:

+ Z10PE Mainboard

+ 64G ECC RDIMM Ram

+ 2x E5-2686v3

+ 4x Rx 480 GPU

 

OK,  I setup XenServer and passed through gpu, sound and usb but I got strange stability issues with gpu drivers.

With a single card it was luck to pass a 3D Mark test successfully.

After a time I got some green artifacts on screen and this was the start of a downward spiral...

 

Than during my research I got noticed about unRAID and after I overcome the fact that it boots from us only,

I realized it worth to give it a try! (maybe you should provide the option to install it as any other os on hd/ssd as well, cause it would give it more trustworthiness at first look...)

But it was one of my best decisions this year to leave xen and go to kvm!

 

The setup was smooth as butter and I got several win 10 VM's up and running with passed gpu's, soud and usb intuitively and lightning fast!

Now I have 4 dedicated desktop workplaces with powerful hard ware and! I can use crossfired gpu's on two of the 4 desktops!

 

So from now I would say: I will buy a license and if this would be a open source project, I would donate cause you did a great job with providing and overall idiot prove package with EXCELLENT documentation.

Thank you for doing this!

 

Now after all the bla, bla, I want to show some benchmark results.

All bench's where running with same settings in default (mainboard bios and driver).

 

single gpu:

 

 

dual CFX:

 

 

dual CFX wih frame pacing enabled:

 

 

When I tried 3xCFX, the driver was unloading and the VM crashing (green artifacts...).

Has anyone get 3x or 4x crossfire running on a VM?

 

To get an idea how Xen is performs, here are some benchs from my first setup with XenServer 6.5.

(XenServer 7.0 still  has problems with usb passthrough so after some short tests I quit my effort on it...)

 

single gpu with defaults (bios and driver):

 

 

(Please don't get fooled by the overall number and focus on "graphics score" - xen seems to have little better cpu handling which has no priority for gpgpu and gaming...)

 

Any comments and discussion welcome!

 

Cheers!

 

 

 

I have an update about 3 way crossfireX.

After clean driver re-install, it was possible to run 3 GPU's for a 3DMark Time Spy shot.

But scaling is bad and the young lady seems to have some kind of parkinson...

Anyway, here are the results with Forced AFR:

 

 

The CPU score is a little low caus it was running with wrong power management settings.

After this, I'm not quite motivated to setup some 4 way benchmark.

 

I tested the 2 way crossfire setup a little more and it seems to be quite robust.

In general I'm quite happy with KVM and don't miss anything compared to XEN.

Performance and robustness are excellent!