External monitor flickers when I close lid on docked laptop

[plsfoldthx]

I have a x201 tablet with ultrabase.

I just got my ultrabase a couple days ago and this happened twice today.

I came back from class and docked the laptop while it was asleep. I resumed the laptop using the power button on the ultrabase and I could see the login screen but it was flickering very badly. So I opened the laptop (which stopped the flickering) and logged in. Once logged in, I closed the lid, but the screen flickered even worse and I was only able to see the top 5% of my desktop. When I opened the lid, the flickering stopped.

Does anyone know what's causing this? Are there drivers I need for the ultrabase?

[Maryland, USA]

I don't know, but my display has seen fewer redocking problems since I switched my cable from DVI to high-quality VGA.