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    Overclocking M17x R4 3940xm

    Discussion in 'Alienware 17 and M17x' started by danyune, Sep 29, 2015.

  1. danyune

    danyune Notebook Evangelist

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    Currently have it stable at 4.6 on every core, but I seem to be running into a different problem that I don't know how to look up.

    Right now, my core can reach 4.6, but when I run prime95, no matter how long, the speed remains at 3.691ghz.

    I have a 330w power supply, an official Dell one, and it says 330w in bios as well.

    Is the laptop CPU just meant to run at that speed if I run at all 4 cores? I can't PM Mr. Fox as the option isn't there, and he seems to be the most well versed when it comes to overclocking.

    I do have an unlocked bios. I would rather have everything done in bios than XTU. My temps are perfectly fine as I have the 10.4 CFM fan upgrade, that I monitor using RealTemp.

    Does someone have a solid overclock on their 3940xm, where the cores will read at 4.0+ on all cores?
     
    danyune, Sep 29, 2015
    #1
  2. MahmoudDewy

    MahmoudDewy Gaming Laptops Master Race!

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    you can tag @Mr. Fox with the "@" ... Indeed he is the one who can provide better insight on your issue
     
    MahmoudDewy, Sep 30, 2015
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  3. TomJGX

    TomJGX I HATE BGA!

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    You are getting power throttling.. There is a 65W power limit on the R4 motherboard and your overclock hits that limit and auto throttles to that speed.. There is something you can do about this, I never was able to figure it out however @j95 has got around this limit but I never got a reply from him on how to get around it.. I believe Mr Fox has some idea however J95 is the one to contact on this... Unlocked BIOS settings need some tweaking but not 100% sure on what these are...

    Sent from my LG-H811 using Tapatalk
     
    TomJGX, Oct 1, 2015
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  4. Mr Pras

    Mr Pras Hardware and systems

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    On the M15x the way to get around power throttling was to snip off the data channel of the AC adaptor.. I'm not recommending you do this (basically you can cut the extra tiny cable inside the adapter connector, or take out the central pin)..

    I've got an adapter like this (from my M15x) so will do some testing when I get a 3940XM (tomorrow).. Don't go cutting your adapter just yet - I suspect that the M17x may not like it. On the M15x it reported as an unofficial adapter but actually that removed the power regulation on the motherboard allowing the CPU and GPU to max out without the power throttling.

    I'll check back in once I get a chance to test it.
     
    Mr Pras, Oct 2, 2015
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  5. danyune

    danyune Notebook Evangelist

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    Ah ok, good to know about the throttle.

    I know it will reach the clock on realtemp doing regular tasks, but once a stress test starts, it limits, presumably due to all 4 cores wanting to run at a higher speed vs 1-2 cores running at top speed from everyday tasks
     
    danyune, Oct 4, 2015
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  6. Mr Pras

    Mr Pras Hardware and systems

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    I'm not sure it's the same on the R4, just a guess
     
    Mr Pras, Oct 4, 2015
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