I915 power consumption issue after switch to systemd?

Question

After switching to systemd I noticed a massive increase of power consumption on my Thinkpad X220 (i5 Sandy Bridge).
The strange thing is, that after some reboots it randomly seems to catch the i915 power saving mode and the consumption gets from ~24W to ~7W at idle. But only after several reboots.
Adding the good old i915.i915_enable_rc6=1 to the boot parameters doesn't make any differences. But looking at the powertop detail outputs it seems to be a i915 issue.
Using the latest linux kernel from core (3.6.4) and latest intel drivers (2.20.12).

Answer 1

I started to get suspicious because I have only ever had the issue in my office. Last week, when I encrypted my drive, my machine wrote to disk for more than 14 hours solid. I then did all the set up and all the restoring from backup etc. with no issue whatsoever. Lenovo ran the thing for 48 hours straight with no problem. But once in my office...
So I asked the local IT people if they could think of anything other than overheating and explained the issue. They took my laptop yesterday , booted it from a hardware testing CD and ran it for a couple of hours sitting on top of a hot computer in the server room which is definitely hot. (It has a whole bunch of computers, I guess.) No issue. They then ran stress tests for a while in the same place. No problem. Highest recorded temp: 65C.
The head of IT then took my power adapter to a more general IT service to be tested and inspected. They looked at it, they opened the plug to check the fuse, they tested it. No problem. Of course, the guy also explained why he was asking and the other IT person said, "Oh, is that on level 1?" "Yes..." So apparently there was another machine (a Mac), I think, doing just the same thing in an office in my part of the building. Testing showed that the power spikes and when the power spikes, the laptop shut down as a safety measure. Solution: they installed a UPS for that one laptop. They didn't tell anybody else, including the local IT people.
What the local IT people were going to do was to install equipment to monitor the power in my office and see if anything weird was causing my laptop to react. However, that was when this was an extremely-unlikely-but-we-are-getting-desperate-for-theories scenario. Clearly, that theory no longer seems wildly implausible at all. So the current hypothesis is that it is most likely that my machine is also reacting to the spikes in power by shutting itself off. (I'm not sure why it should have just started doing this but who knows what the state of the electricals is and how that might vary?)
I have been told that a surge protector will do no good. (They've given me one anyway but apparently it will not deal with spikes in phase 3 power or something - I didn't understand this bit but the head IT person said he didn't understand it either but the electricals IT person showed him with graphs on the whiteboard. So it must be true.)
The current plan is to try to get the UPS from central IT which was provided for the other laptop since that person's discipline has since moved to another floor of the building so the UPS probably went back to central IT. They are going to ask during a meeting tomorrow about this possibility. Otherwise, they are planning to order a UPS for me on Monday.
I'm somewhat surprised that the abrupt shutdowns haven't screwed my data. I've lost work but not seen fs corruption. I didn't take my laptop today. I'll need it next week but I do not plan to plug it in in my office until I have a UPS.
I'm pretty annoyed, to be honest. I've wasted hours on this and got incredibly stressed about it. The IT people have also wasted a (smaller) amount of time. I hoped to have a new draft of an article I'm working on written by the end of reading week but that didn't happen due to all of this. And they *knew*. It would be different if this was an unknown problem just discovered - of course, one could understand that. But there's a known problem which can cause this type of problem and presumably could well damage equipment without these sorts of safety shutdown features and they don't tell anybody.
And, no, I doubt very much indeed that a damaged personal machine would be considered the institution's liability. (Maybe if it was a student's machine and the student was required to use it or something but even then...)
I can't believe it does much good to their equipment either.
The local IT people did know there was an issue with some burnt out devices but that was about eight years ago and only got mentioned as a outside possibility when other diagnostics turned up no result.
What gets me is that the proposed solution will only solve the issue for me - not for anybody else in my part of the building on level 1.