L2251p not waking from sleep on Displayport

[dsk]

We have a fleet of M58 and T410s with L2251p monitors connected via Displayport.  As we're rolling our OS over to Windows 7 x64 Enterprise we've begun to see an issue where the desktop and laptop machines are entering a sleep power state, the monitor follow suit, but when waking the machine the monitor needs to be power cycled to become useable again.  This is not an issue on shutdowns or restarts only waking from sleep.  We've also noted that connecting via VGA does not cause this issue, it seems to be related to Displayport.

Any suggestions?

[pb33]

We experienced the same problems with with the M90 and different Laptop Models. Updating the BIOS and the Intel Display drivers to the latest versions solved it.

[wesmon]

I have experienced a similar issue with my L2230x which I think may be related. My L2230x is connected via VGA port and USB port. Sometimes when Windows wakes up it thinks it has two displays connected and it will present the login/unlock prompt on a display that is not the primary. Try disabling the "password on wake". Try adjusting which display win7 thinks is primary.

[zricov]

Hi,

Can you confirm this on multiple machines? I've just updated the latest drivers and BIOS for a X220. Still having the same issue.

22inch L2251p (widescreen) connected using DisplayPort (came with monitor) to X220 dock. Won't wake when goes into standby.