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Joined 1 year ago
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Cake day: July 5th, 2023

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  • I think the N100 type CPUs are limited on PCIe lanes. You end up with less nvme, less sata, and usually no slots.

    You can find x570 am4 boards for less than $100 now. Two nvme, 8 sata, 2 big slots and 2 small.

    But all of that flexibility and expandability is going to cost you in power. My 7700x w/A380, 3 hdd is 125 watts 24/7. $10 a month on my power bill. I think those n100 mini PCs only have a 35w brick and idle at less than 15w.










  • It depends where you measure. If you measure across the inductor, it absolutely goes negative.

    The frequency is generally fixed, the duty cycle will vary.

    A variable speed drive can be fed with DC. Is the output AC or DC? I know you need a three phase AC motor to wire up to it.

    Is audio DC? It doesn’t have a fixed frequency. Amplifiers pulse DC and then remove or ‘block’ the DC offset so speakers see AC.

    It seems like people in this thread have a very strict definition of AC being a 60Hz sine wave, and everything else must be DC.


  • Is a square wave not AC? Current is flowing in and out of an inductor 100k times a second.

    Could that 100khz square wave excite a transformer and produce usable current on the secondary? Absolutely it could, and that’s how a bigger SMPS works.

    If you’re looking for a “pure DC to pure DC” converter, that’s called a linear regulator and it’s wildly inefficient. They work by varying the conductance of a transistor but are useful for low currents. The extra voltage is converted to heat.