Waking up from suspend crashes in 15.04

[kbuntu1]

I have a new install of Xubuntu 15.04 on a new IdeaPad Z50/70. (I installed 15.04 because that's the only version that I can get my wifi working on), and am having several problems.

When my laptop wakes up, it shows the desktop but the computer freezes. I cannot use the mouse or keyboard. I have to hold down the power button to forcibly shut it off.

[kbuntu1]

I'm still having this problem.

The computer seems to be completely frozen when it wakes up. I can't even ping or ssh to it.

[lolc]

I encounter the same problem with Xubuntu 15.04, at times. Before the upgrade, Xubuntu 14.10 worked fine.

[kbuntu1]

Still having the problem....

[1-contacto-carlosgonzalez]

Same here, but using Kubuntu 15.04

[damian20]

Exactly the same problem on my laptop (Dell Latitude 3450 with fresh xubuntu 15.04). I though, it's connected with screensaver, so I unchecked screen locking option - with no luck. :(