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Why do my newer laptops run cooler then previous laptops?

  1. Apr 12, 2015 #1
    The last 2 laptops that I've bought (both HP) run noticeably cooler then previous laptops that I've owned (Toshiba and Dell). In fact I feel no heat on my legs at all from either of them. Did some new technology come along in the last few years that allows the batteries to produce less heat or allow the machine to use less current? Or is HP just better about temperature management then other manufacturers?

    Is this a difference between manufacturers or a difference between newer and older technology?
    In either case, what IS the difference?
  2. jcsd
  3. Apr 12, 2015 #2


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  4. Apr 12, 2015 #3
    Efficient power management has always been an issue for laptops, so all the manufacturers have been working on improving efficiency of components.
    I think you are just talking of overall improvements in technology rather than that a particular manufacturer is strides ahead of the others.
  5. Apr 13, 2015 #4


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    At one time, processors were running constantly but now, when there's nothing important going on, a processor will slow right down. Each cycle in the processor is allowing some charge to pass from the power supply and this (E=QV ) Energy needs to be dissipated. Fewer cycles per second will mean less power dissipation. Also, turning its peripheral circuits off can help significantly. An LED lit screen will use less current than the old CFL back-lit screens, too.
    Mobile phones get very warm when you are playing a processor-intensive game and it's not just the screen that's using the current. That's a good reason to not be playing Candy Crush Saga every hour God sends. Haha.

    The internal resistance of the battery could also count in the heating effect. I wonder whether Lion batteries happen to have a lower internal resistance than NiCAds, too? I'd bet some PF member would know about that ?????
  6. Apr 13, 2015 #5

    Doug Huffman

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    The thermal interface paste between the CPU/GPU and cooling system has not yet dried and shrank away from the contact surfaces. More basically, the radiator fins have not yet clogged with dust and hairballs.
  7. Apr 13, 2015 #6


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    Low power design technology has made huge progress in recent years, especially the available tools.

    Variable voltage designs, variable frequency designs, clock gating, power gating of complete functional blocks, etc have all been applied to the latest processors and peripheral controllers. Also the smaller IC geometries consume less dynamic power and leakage power is controlled.

    The driving factor is debatable, but is largely battery life and battery costs. The end result is a cooler lap(top).
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