T400 CPU heat problems

[mariol90]

I have a bunch of T400 laptops that all have the same problem: the processor heats up extremely quickly, and it will either throttle or shut the computer off completely after a few seconds of high CPU load. These are all older T400s (dec. 2008 and jan. 2009) with T9400 CPUs and ATI switchable graphics. The GPU seems to be fine as far as heat. Was this a common problem or anything? I repasted one and ran LinX, it shut off after ~15 seconds.

edit: the BIOS is updated on all of them. I tried another T400 (intel GPU, P8600) with the same battery and hard drive, that one works fine. Core temperatures max out around 70C.
I also switched a T9400 with a T9550. It throttled after the same amount of time but took over a minute until it shut off.

After reading a bit on throttlestop I tried it out and it helped:
http://i.imgur.com/qC4FR.png before throttlestop, tpfancontrol flips out
http://i.imgur.com/GRwy5.png after stopping LinX, tpfancontrol goes back to normal
http://i.imgur.com/PduV4.png with throttlestop, everything seems to be good for the most part.

[Cigarguy]

I got a T400 with a T9400. Nothing out of the ordinary with regards to temps (72-76 deg C under full load). I'd suspect there is something drastically wrong with the cooling system. Make sure the thermal paste is applied properly and the heatsink fan assembly is assembled properly. It's real easy to bend the cooper heatsink out of wack or apply to little/too much thermal paste.

[mariol90]

Apparently it's not a heat issue, since throttlestop completely fixes the problem. It's something with how lenovo has their motherboard set to control the processor. It is odd that multiple computers have the same exact problem though.

[Cigarguy]

Don't have any problem with both of my T400. It's running with temps as expected at stock settings.

[mariol90]

I've never had this problem with any other T400 either, only this specific type (2767-A15) and manufacture date - late 2008/early 2009. All I can do for now is have throttlestop run on startup which is better than nothing. The computer seems to be fine with normal usage too.

[mariol90]

I still haven't been able to figure this out. Some will work fine with throttlestop but others will shut off anyway, even if I'm just installing updates. The one I'm working on now shuts off sooner if the dedicated graphics are enabled and it gets hot.

[emeraldgirl08]

I have a T400 equipped with a T9400 CPU and ATI switchable graphics as well. I do not experience any shutdowns as you describe. It does seem odd that you have a pool of T400 which suffer from the same symptoms

Have you tried setting the BIOS back to default? Does the shutdown occur in BIOS? Have you tried an alternative OS to see what happens? It seems it might be hardware related but a pool that share the same problem is pretty odd? Did you purchase the batch of T400 from the same source?

If you figure out what is going on please post your findings. Thanks

[mariol90]

it is odd, and i've been using one with windows 8 for the past few days, it hasn't had any problems at all. throttlestop is running and that may help.

Have you tried setting the BIOS back to default? Does the shutdown occur in BIOS? Have you tried an alternative OS to see what happens? It seems it might be hardware related but a pool that share the same problem is pretty odd? Did you purchase the batch of T400 from the same source?

If you figure out what is going on please post your findings. Thanks

I did reset the BIOS back to default, and it never shuts off while in the BIOS. One did shut down while installing windows from lenovo recovery discs. that seemed to be from overheating since it was extremely hot, and integrated graphics only was selected in the BIOS so it's weird. haven't tried any other OS. they are all from the same source. i've had 2 others from the same source also, one 2008/12 and the other around 2009/09, the latter was perfect while the former had the same issues as these.
I'll try to work on the other ones today and post what comes up from all of them. What is the date code on yours? I'm curious if it has anything to do with this.

edit: I ran LinX on the T400 I've been using for a few days. The first time, it shut off after around 1.5 minutes, and the 2nd time it was probably 30 seconds (at 2.4 ghz, lower voltage too). The CPU temperature was 91C at its highest so that should be fine. The screen goes black when it prepares to shut off, then sits there for around half of a minute and proceeds to turn off.
I also ran LinX on another T400 which doesn't have throttlestop, it shut off too. Everything is fine if the max CPU speed is 1.6 GHz.