Right now Im preparing for Microsoft Management Summit next week in Las Vegas. Sure it will be a tough time being in Vegas again with lots of hard work (and play) and another keynote appearance :)

Anyhow, Im also preparing one of the booth demos. This one will be showing the Microsoft VDI stack, inclusive of Windows 7, App-V and Windows Server 2008 R2 SP1. This demo features Dynamic Memory and RemoteFX all working together with the RDS Connection Broker. Cool demo! Though I had one problem with it as I went to enable RemoteFX.

I built a shuttle server for the demo that has the AMD Phenom II X6 proc (which is pretty fast) 16GB of RAM and two ATI FirePro v5800 video cards in it. Yes two! When I configured it I figured that I should hook together the video cards, CrossFire style for best performance right? Wrong! As I started the Windows 7 SP1 VM it hung. I mean it just stopped. I checked over the drivers; CrossFire wasnt enabled so I enabled it. No difference.

I then opened up the case again and removed the CrossFire cable between the cards and hey presto! It worked. Turns out that RemoteFX doesnt gain any benefit and is not designed to use cards in aggregate like this. Its designed to use each card individually via the hypervisor.

So there you have it. If you have a multi card setup for RemoteFX, dont hook them together. It wont work if you do.