PCB Breakdown: Asrock "6"+3 phase AM4 VRM used on the AB350M Pro 4, AB350 Pro 4 and AB350 Gaming K4


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  1. came back to this video to check on the amperage of this regulator, wanted to know how high I could safely raise the EDC on one of these boards…looks like the answer is "don't" because the default is 140 and your calculations say those things shouldn't put out more than 156

  2. 14:38 not exactly ice cold, but with 4 sticks of Crucial Ballistix Sport LT during a Memtest86 Pro 8.1 run, the "hottest" parts are the 2 inductors, and they're just barely above body temperature with no forced airflow whatsoever

  3. As we look back after some time, this board has become one of the most popular budget boards on the market. The design might be misleading, but it showed its strength and it has a great value for Ryzen 5 CPUs.

  4. Which specific SM4337 & SM4336 are used? Can't read subnumbering. I'm interested to know the max sustained temperature allowed for 24/7 for years to come.

  5. I'm using an 8 core 1700x on this board. No problems so far, but VRM temperatures, read from lm sensors on Linux, says 94 to 104 degrees C. Aux2 says 80 degrees, which I think is the SOC Vrm temp. I tried better cooling on the vrms, but that made little to no difference on the temperatures. But it seems that on Windows CPUID hwmonitor gives different temperature readings (not tested). So it could be that Ubuntu 18.04 just has not correct VRM readings for this board.

  6. cpI have the AB350M pro4 MB with Ryzen 5 1600 and Corsair Vengeance 2666 memory (16mb). I have OC'd CPU to 3.7 Ghz. Since this MB doesn't have sensors to measure VRM temps, am I safe at this OC speed?

  7. i love how soc vrm story contradicts your conclusion from 5 minutes before for vcore "6" phase vrm "useless extra components" xD

  8. What is bes VRM designe for 2400g, on cheap MB-s? ASROCK B450M-Pro4 mybe? (it has 3 phase and heatsink) yea bad designe but would it handle 2400g like ok?

    Or mybe Msi B450A-PRO with better cooling?

  9. LoL. Just got this puppy in my workshop with a blown 1st phase (I mean AM350M Pro4). At first I was surprised (assuming it was a 6-phase), but then I saw those traces between chokes, and once I cleaned up the soot off mosfets – I've noticed the familiar Niko-semi 0903 and 6188 firecrackers )))
    So, my specimen is even more cheaply made than the one in your review, Buildzoid ))))
    It's probably going to become an actual 3-phase board, as soon as I get the VRMs cleaned up and fixed , and go into my office PC w/ 2400G.

  10. Can you give me a quick break down of this budget board I'm looking to purchase.

    I have just started looking into vrms and mosfets. I understand basic electrical terminology and I have completed a few classes on electrical theory.

    You sir have an excellent way of explaining things 🙂

    78LMT-USB3 R2
    $59.99 on Amazon.


  11. I've been running my 1600@3.95 GHz now for over a year on that board. VDROOP is absolutely atrocious, but apart from that it seems to be doing it's job rather well. But i'm going to see what B450 has in "store" and this time will make sure to by a proper board…

  12. I cannot find the quality of the components but the MSI did a similar "trick" on their x370 SLI plus mobo which is 8+2 by the voltage regulators but the PWM segment is 4+2 dunno about other components… can you review this mobo, as it is popular… and what about it with the 2700x is it a good combo? MSI x370 sli plus

  13. Tweaktown has a different view https://www.tweaktown.com/reviews/8173/asrock-fatal1ty-ab350-gaming-k4-motherboard-review/index3.html


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