Thinkpads Forum

Hey guys I was wondering what do you usually get as far as idle temp on a T420 right now im getting roughly 46-50 celsius, if you know how to lower the temps lemme know. Thanks guys.

I used my T420 for about 45 minutes and then stopped long enough to eat breakfast and checked the temperature after. I'm running Ubuntu Linux 12.04 64-bit and have the Core i5-2520m (2.5 ghz) processor as shown in sig below. I see "idle" temp at 42C. Note I didn't close my browser window for the test... What temperature are you expecting to see at idle?

This review from Notebook check discusses a Thinkpad T420s with Core i5-2520M at idle with a CPU temperature of 45C http://www.notebookreview.com/default.a ... review&p=5. Unfortunately in their T420 review, which uses the same processor, they don't mention CPU temperatures http://www.notebookreview.com/default.a ... ess+laptop.

Speedfan and Speccy report an average temperature of 55 degrees on my i5-2520m discrete graphics T420. Doing light browsing and the occasional netflix, which makes the GPU kick in.

Bear in mind that CPU temperature is highly influenced by ambient temperatures. The tests carried out for these reviews are done in a controlled environment, usually at 25 degrees celsius. Don't expect the same results as the test run.

I've been in a room without air conditioning all day and it is a warm day out here in New York, running mostly on AC power and sitting on a couch with the laptop on the table or on the cushions, so the fans may not be working to the best effect sometimes. Usually while sitting in an air-conditioned room i get 42-47 degrees, again depending on what I'm doing. I've set the fan Control to Passive when the charger is disconnected, and most of the time the fan stays off, although it does kick in occasionally.

long story short - too many variables in everyday use to consider a general temperature range of operation. unless the fans are running at full pelt from the moment you power on to shutdown, I wouldn't worry too much.

wolfman wrote:I used my T420 for about 45 minutes and then stopped long enough to eat breakfast and checked the temperature after. I'm running Ubuntu Linux 12.04 64-bit and have the Core i5-2520m (2.5 ghz) processor as shown in sig below. I see "idle" temp at 42C. Note I didn't close my browser window for the test... What temperature are you expecting to see at idle?

To add to what dxps26 said, this test was done in an air conditioned room (75F) and on a Thinkpad T420 with Intel integrated graphics. I agree if fan isn't running full bore all the time I wouldn't worry about the temps till they were a problem.

Thanks for the insight guys makes things a lot easier on my part. I thought I got a defective computer. I live in Hawaii so im assuming that 48c isnt so bad with room temp.

I confirm T420 has bad cooling system - or got worse in time
i had to apply mx-2 twice to make sure i excluded the possibility of bad paste - the paste is ok but in the summer i got 80 C under load and around 55 C idle
My T500 has a superb cooling system that gets around 46 C idle in the summer - mind the processor is 50% the ability of the i5

1. Use PTM7950 instead of thermal paste

2. It could be both: the heatpipes could have degraded over the years, and CPUs do degrade over time (electromigration). Good thing the T420 has socketed CPUs, and making it trivial to replace the processor if it goes bad.

For testing set your graphics settings towards maximum battery and performance rather than quality. The graphics are probably working hard as the system is getting dated. I actually even do this on all computers now and even my T42 and I don't have issues with high temps.