Low VRAM video blank after 4-to-5 upgrade in Win6+ guest OSes.

Discussion in 'Windows Guest OS Discussion' started by ehurtley, Mar 19, 2010.

  1. ehurtley


    I've been using Parallels since day one.

    I think it's great.

    I've never had a major issue with the product itself, until now.

    I use it to run a small test network of a variety of guest Windows OSes, from Windows 2000 to Windows Server 2008 R2 and Windows 7. (Yes, all legally licensed, thankyouverymuch.)

    On most of my guest OSes, the VM is configured to be 'minimal'. The smallest amount of RAM the OS supports, only 2 MB video RAM, 3D acceleration off, etc. This worked just fine in Parallels 4. (See attached screenshot - horizontally cropped to fit within the forum's max width; hrm, why did I take that with my Vista VM off?)

    However, after upgrading to Parallels 5, and updating the VM tools, I have an odd symptom. The Windows 6.0 and higher guests (Vista, Server 2008, 7, and Server 2008 R2,) I get no video on my 'minimal' configurations. My 'big beefy' configuration, with full video acceleration on and 256 MB VRAM set, works fine. But my 2 MB VRAM, no 3D configs are just blank. Even stranger, I can't use the menu bar, or the individual VM's tool bar, or any Parallels function, when one of them is active! In order to recover Parallels to usability, I have to either remote in to the VM and shut it down, or Cmd-Tab out of Parallels, then click on the VM list, then right-click on the offending VM in the Parallels VM list and shut it down from there. (i.e. if I make a "no video" VM the foreground Parallels window, all of Parallels becomes unresponsive, I can't even make a "good" window come to the foreground unless I switch to another application, then click directly on a "good" Parallels window.)

    I have played with the various VM settings, and the only one that makes the VM usable again is to give the VM at least 8 MB of VRAM. Again, this happens in all Windows 6.x OSes (Windows Vista through Windows Server 2008 R2.) While I will grudgingly accept this in the 'desktop' OSes, Vista and 7; it seems very unnecessary in the 'server' OSes. (All Microsoft says about video requirements on the server OSes is "800x600 or higher". And that is a great resolution to run in Modality, by the way. OS elements are just big enough to be usable when shrunk to Modality size, and I can tile a bunch of VMs, as shown in my attached screenshot.)

    I know, this may seem like grousing ("Oh no! I have to use up 8 MB of VRAM per VM!") but when you're running 6-10 VMs at a time, that adds up. For just the four such affected VMs I use right now, that's 24 MB of my video card's limited VRAM. I can see the need to bump to more VMs soon. And I still want to be able to actually *USE* my machine at the same time.

    This is on a 2009 Mac Pro with the fastest processors, 12 GB RAM and a GT 120 video card. (Yeah, I know, for what I'm doing, I really need more RAM and a better video card. It's not in the budget at the moment, I have to make do with what I have. The point is, I shouldn't need the better video card.

    Attached Files:

Share This Page