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  • Flunk - Saturday, February 11, 2017 - link

    "The 780 W external PSU is rated for a 39 A maximum load (below that of high-end desktop PSUs)"

    This sentence doesn't really make sense. It's 39A because the power supply puts out 20V and 39 x 20 = 780 (shocking, I know). The AMP ratings you're thinking of on desktop supplies are probably on a 12V line. That doesn't mean that this is any less capable. Just that you don't understand the relationship between volt, amp and watts (W = A x V).
  • Valantar - Saturday, February 11, 2017 - link

    My thoughts exactly. That sentence makes no sense at all. Were you comparing it to the A rating of the 12V rails of an ATX PSU? If so, that's a completely invalid comparison.

    The same goes for it not being 80+ rated. 80+ is a rating system for internal ATX power standard PSUs (outputting at the very least 12V+, 5V+, 3.3V+, 12V- and 5Vsb. That an external non-ATX PSU delivering a single 20V rail isn't certified by that standard is... well, not all that surprising.
  • Samus - Saturday, February 11, 2017 - link

    Typically these are rated by class. Class II, Class IV, Class V, etc. Being 90%, it is Class V.
  • Valantar - Monday, February 13, 2017 - link

    So, in other words, it can't be sold in the US? The US mandates all external PSUs sold there to be class VI, after all (http://www.cui.com/catalog/resource/efficiency-sta...

    Actually, scratch that. From reading that document, the requirements for Class V is 87% average and =<.5W at no load, but that only applies to PSUs up to 250W. The Class I-V ratings don't go higher than that. Class VI mandates 88% average efficiency between 49 and 250W, 87.5% average efficiency at above 250W, and at most .5W under no load, for single-voltage AC-DC PSUs. Which places this PSU clearly in compliance with Class VI requirements. Sounds great to me! Of course, overall efficiency is all dependent on the efficiency of the DC-DC converters in the laptop in question too. But that's outside of anyone's control except for hardware manufacturers, unfortunately.
  • Samus - Tuesday, February 14, 2017 - link

    All we have to go on is the manufacture claims, which are 90% efficiency, which is well beyond class IV. But I agree, it doesn't really qualify for classification efficiency because it is such a broadly unusual product. Most single voltage power supplies of this output simply are not rated, such as battery chargers, jumper boxes, voltage converters (typically DC to AC) and so on.

    But since it is a PC product and we are so used to a rating of sorts, I still feel it closely resembles Class V more than anything, but without the details of no load efficiency, as you said, it could very well be Class IV with a high efficiency at load.
  • Valantar - Thursday, February 16, 2017 - link

    I think you misread my comment. Class I-V don't go higher than 250W, but class VI (i.e. 6, the most recent and highest rating) has a rating for ">250W" output power supplies (as well as other new classes like multi-voltage power supplies). Which this (given that its 90% efficiency claim is accurate) passes with flying colours. The US mandates all chargers sold there to fulfill Class VI requirements.
  • close - Monday, February 13, 2017 - link

    Well the comparison might not be apples to apples but this PSU is rated at 780W while many high end desktop PSUs are rated at a lot more. So "mathematics wise" 780W (39A at 20V) is equivalent to 780W (65A at 12V). With desktop PSUs putting out as much as 166A at 12V (almost 3 times as much) I think the remark is valid.

    This is probably the highest end laptop PSU on the market but it's still a far cry from high end desktop PSUs. Or at least this is what I read from that remark.
  • Valantar - Monday, February 13, 2017 - link

    If read in that way, sure, the statement is valid. But what on earth is the point in effectively saying "This 780W PSU delivers less power than desktop PSUs rated for higher wattages"? Or more to the point: "This PSU delivers less power than more powerful PSUs." In what corner of the universe is that an even remotely useful statement? Of course it's a far cry from high end desktop PSUs. Is the 780W rating even remotely confusing in that regard?
  • close - Monday, February 13, 2017 - link

    Maybe to show that ultra-enthusiast laptop PSUs still lag behind high-end and mainstream desktop ones? It might have literally been just to state the obvious.
    I will try not to assume that an AT editor forgot that V is half of the P formula or that you can't judge a PSU only by its amps :).
  • vladx - Saturday, February 11, 2017 - link

    Is there even a need for a 780W PSU? I think a 450W/500W would've been enough for any new laptop on the market.
  • lazarpandar - Saturday, February 11, 2017 - link

    Eurocom sells laptops with desktop CPUs and multiple GPUs (which are desktop parts as well if I'm understanding Nvidia's marketing correctly). They currently sell laptops that require two 330w power supplies to run.
  • RaichuPls - Saturday, February 11, 2017 - link

    6700k + 2 x GTX 1080 laptops exist. They require more than 500w to run.
  • CookieBin - Sunday, March 12, 2017 - link

    Try a Laptop with a Desktop CPU, and 2 1080 MXM modules in SLI. (There are several designed by MSI, EVOC, and Sager.)
  • sna1970 - Saturday, February 11, 2017 - link

    $475 ? are you insane ?

    Just design an External case that takes SFX power supply

    750 W SFX power supply = $100

    External case = $50

    Total $150
  • keeepcool - Saturday, February 11, 2017 - link

    And a laptop wants 19-21v and an ATX PSU will give you 12v, a bit under.....
  • Penti - Sunday, February 12, 2017 - link

    Seems kinda pointless, much of the beefiness comes from the fact that their laptop power bricks and laptops use 20V voltage. Maybe they should just go 48VDC? And 1.7 kg on top of the 4 kg notebook? You do have to carry around both.
  • zodiacfml - Monday, February 13, 2017 - link

    If they have to build this then there is a market. I wonder who buys these.
  • CookieBin - Sunday, March 12, 2017 - link

    I preordered this immediately, because I refuse to carry two bulky messy wire supplies with my gaming laptop.
  • BrokenCrayons - Monday, February 13, 2017 - link

    That's one over-the-top power supply. Even my Dell Precision didn't need more than 135W and I recall thinking it's power brick felt huge.
  • BurntMyBacon - Monday, February 13, 2017 - link

    It WAS huge, but also passively cooled. This brick saves some space by being noisy (active cooling). That said, we are quickly approaching standard (construction) brick weights (1.7Kg vs ~2Kg) and we've passed standard brick volumes by ~42% (1518cm^3 vs 1069cm^3).

    http://www.beldenbrick.com/brick-dimensions-guide....
  • BrokenCrayons - Tuesday, February 14, 2017 - link

    True enough. If you take passive cooling off the table as a requirement, you can indeed cram a lot more PSU in the same space. I wonder how much noise that 780w monster makes.
  • CookieBin - Sunday, March 12, 2017 - link

    It doesn't make any noticeable noise. At least with my testing on a 660 Watt laptop. The fans in the laptop create far more noise than the power brick. However, I did encounter a brownout while using the power supply. Probably need to play more games for further testing.
  • watzupken - Friday, February 17, 2017 - link

    I feel the product is pushing the boundaries of the laptop market. It is definitely for a desktop replacement, but I certainly will not fork out that much money for a PSU. The cost of the PSU is 1/3 of a setting up a desktop with very decent specs.

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