Performance problem when connected to projector

[wallacekelly]

My guest OS (Win7) works great on my host OS (Win8). Absolutely amazing! Except....

...today when I showed up to a customer's site and plugged my laptop into their projector. Major disaster trying to do a demo...

As generally occurs when connecting to a projector and setting host to clone to both displays, my host resolution automatically resized from 1440 x 900 (my laptop's native resolution) to 1024 x 768 (the projector's native resolution.) That all worked fine. But once I started to work inside my guest OS, I found it sluggish. No, make that it started crawling on all fours. Try to start a program that generally comes to life in 3 secs... took 15 secs. It was unusable. I disconnect from the projector. Restart my guest OS, everything is fine again. Reconnect to the projector, and once again the guest OS is really slow.

I'm assuming it has something to do with the VirtualBox display driver? Perhaps the hardware acceleration gets disabled?

I've tried everything I can think of... adjusting the video memory in both directions..., forcing the projector to use my laptop's native resolution..., changing the color depth from 32 bits to 16 bits...,

Any ideas what to try next?

Thanks!

[Perryg]

Hard to say since Windows 8 is not a fully supported host yet (not even an operating system yet), but I would think that has something to do with it since all the VirtualBox drivers talk to the host.

My understanding is only minimal consideration has been taken from the development side of VirtualBox to properly address them since Win 8 is still in development. I would be interested to know if it worked properly on a supported guest though.