Step 4: Clean that machine
I'm getting ahead of myself, though. Before I inserted the new keyboard, I noticed five years of accumulated dust bunnies and much worse. So, while it was still wide open, I cleaned out the R50's insides. About 5 minutes is all it took.
This is the most important part of extending the longevity of a notebook, because if garbage is blocking the cooling fan, the system can overheat. I suspect that this was responsible for the R50's unexpected shutdowns.
How to do it
With the keyboard off, go through every nook and cranny with a can of compressed air. I suggest wearing a dust mask and doing this chore outside because the dust -- and everything else trapped inside the case -- will fly. I guarantee that you'll be amazed at how much junk comes out.
After that, I attacked the R50's loud fan. I pulled a wad of dust out of the fan's blade, but I decided to be thorough because it'll likely be another five years before it gets cleaned again. After loosening the three screws that hold the copper heat pipe onto the processor, I blew even more detritus out. The fan blade now turns silently.
It's now time to clean the case. Lenovo Group recommends using diluted dish washing soap, but it can't cut through the grime that has probably built up on your notebook's case. I prefer something a bit stronger, like Fantastik.
By the same token, a good way to get rid of scratches is to use a mild abrasive, like toothpaste or Soft Scrub, but in both cases, rinse the cleanser off with a damp sponge or paper towel when you're done.
Don't use any of these harsh cleansers on the screen. There are several name-brand spray-on cleaning fluids for LCDs, but they're generally nothing more than a 50:50 mix of isopropyl alcohol and distilled water; both are available at any drug store. Just spray a little on and wipe it clean, but make an effort to get into the corners and clean the display frame. Your eyes will thank you.