Latitude E6220 Problems waking from sleep

My Latitude has been having an intermittent issue recently when waking from sleep. When I open the lid and press the power button to wake it up, the power light comes on, and so does the caps lock light, but the screen will not come on, or even wake up at all. When I hold the power button to shut it off, no response. I have to remove the battery. When I power it back on, same issue. There is no BIOS screen or any activity. The only way to get it to work is to re-seat the RAM.

Thinking the RAM might be bad, I ran the Dell diagnostic through the full test suite and it found no errors. Curiously, it then warned me it had shut down due to a thermal event earlier. There should not be a thermal event while it's sleeping. It idles around 50*C, which I think is normal? I can re-do the thermal paste, but I don't think it's over-heating. Could a DIMM slot be failing and making it think there is a thermal event? Very confused... :/

 

I recommend you use MemTest86 left to run overnight.

For me, this revealed a problem RAM module that shorter diagnostic tests reported was OK.

John

 

I did MemTest86 with 4 passes and no errors found. Oddly enough, the EUFI boot version froze immediately starting the test, but the Legacy BIOS boot version performed perfectly. I am noticing that under heavy load, my CPU temp nears 98C. This seems very high to me (TJMax is 100C isn't it?), even for a laptop.

Are Latitude cooling systems woefully inadequate, or should I be looking at re-doing the thermal paste? I have cleaned out the inside of the computer with compressed air. No dust to be found.

 

Latitudes normally have decent cooling systems and 98C is unusually hot. Did your cleaning include the heat exchanger grille on the heat pipe? If not, do it, otherwise the thermal paste is next in line. Don't apply too much: It should be the thinnest possible layer needed to fill any gaps between the CPU and the heat sink.

John