Dell 1745 over heating probs

Im using a Dell 1745 laptop which is over heating underneath and switching off. Stays on around half hour. At the minute Im on a old laptop and running a diagnostics on the 1745, i only hope it stays on long enough to get the results of it. I was needing a new battery which is in now , thought that was my problem but surely isn't, any advice or pointer in the right direction would be helpful. thanks

 

Clean the fans out, Physically removing the fan and cleaning the heat pipes is the best option.

Also if your comfortable opening up the laptop, you may want to consider a fresh application of thermal paste

The service manuals are available in dells Support site by model number

 

thank you for your reply, that was kind of you, what i done was take into my local shop so he cleaned it all out , what a diff now :0) however now im doing a reinstall of windows 7 and im lost as to what order to put on the drivers. I done a fresh install last night but up came this PNP monitor that has caused me all sorts of probs see below so only way i think to get rid of it is to again fresh instal but rather than drivers off disc , im downloading all drivers from dell website and try again, im not able to load a few drivers because of this other monitor that should be there, im on a 17 inch laptop. if you can give me any tip i would be grateful, just the order to put on the drivers
thanks :0)

 

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