Vostro 1700 hot CPU?

I've inherited a Vostro 1700 with a Core 2 Duo T7500. It seems to idle about 47° C CPU temp. (That's running Ubuntu 10.10. If I boot XP, Everest reports 54°.) That seems high as my Thinkpad T500 (Core 2 Duo T9400) runs about 33° C while idling.

I can hear the fan if I hold the laptop up to my ear.

Is it time to clean the lint out of the CPU cooler or is this normal for the Vostro 1700?

thanks,
hank

 

It's normal that the T500 should have a lower idle temp thanks to the T9400's smaller process node. I don't think a 47C idle is bad for a T7500. What're the load temps, though?

 

Can you list your load temps and your ambient room temperature?

With 23.5 C ambient, after repasting my T7500 and undervolting it I got it to 27-28C idle.

 

CPU temperatures are driven by 3 factors: (i) The settings in the BIOS that control the fan; (ii) the amount of heat being generated; and (iii) the effectiveness of the cooling system.

You may find that the T500 stays cool because the fan keeps running at a low temperature (sometimes this is set to happen on mains power but not when running on battery) whereas the Vostro 1700's fan cuts out at a higher temperature. Idle temperatures are therefore controlled by the rules in the BIOS but temperatures under load are more affected by the effectiveness of the cooling system.

John

 

Thanks for the replies. It does make sense that the system would use less power if the processor was allowed to run at a warmer temp. Ambient is about 20° C (68° F.) I haven't run with any heavy loads and I didn't want to do so if there was an obvious problem.

thanks,
hank

 

That is a little worrisome, 27C idle over ambient? I would get canned air/air compressor and blow out all the dust in the fans/heatsinks/heatfins. Also if it worries you alot, you can go repaste your CPU, doesn't take that much effort on the original Vostro line.

 

I started transcoding a DVD and the temp went up to 93° C in a minute or two before I canceled the job. I think I need to open it up to the point where I can clean those fins out at a minimum. It might be wise to repaste the heat sink too as I know the PO used to use this for ripping DVDs. I don't think he was in the habit of checking CPU temperature and I suspect this might have seen many hours of operation at temps near the 100° C limit. It's possible that thermal cycling has compromised the connection between CPU and heat sink.

Again, thanks.

-hank

 

I agree that 93C is too hot which either indicates a clogged cooling system and/or a poor thermal connection between CPU and heatsink. See the service manual for instructions about how to get at those parts.

Whatever CPU temperature you then get, you can probably drop the maximum temperature by another 10C by undervolting the CPU.

John

 

If you are feeling generous, I'll take the Vostro 1700.

With Prime95 my T7500 only gets 71C max..

 

IMO not something I wold characterize as "not much effort." Not when it requires removing the display, palm rest, keyboard, disk and DVD drives, bluetooth card... But it needed to be done.

maybe both:





It looks to me like the thermal paste did not provide good contact between processor and heat sink. Perhaps that bubbly appearance was caused when I separated the two, but the paste had a sort of rubbery texture so I suspect that may have been left from a previous separation, perhaps during system service.

Thank you for your generous offer!

I applied some Arctic Silver and it's going through the break in period. At idle, it was hanging in at about 40° C. I'm ripping a DVD right now. Previously the temperature shot up and I broke off when it exceeded 90° C. After cleaning stuff up and repasting with Arctic Silver, the temperature rises gradually to 79° C.

(maybe it's time to perform the same service on my T500.)

best,
hank