Question USB ports on motherboards

May 10, 2021
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Hello guys!
I recently built a PC with a Ryzen 3 3200G and an Asrock B450 Steel Legend motherboard. There are in total 4 USB 3.1 ports in the back of it. The issue I'm having is that, whenever I connect any device to the bottom two USB 3.1 ports of the motherboard and I turn off the computer, the device still gets power. Whereas, if I plug the same devices to the top two USB 3.1 ports, they don't get power after turning off the PC. The reason I'm even posting this is because whenever I have my keyboard and mouse connected to the top two ports and I put the pc in sleep mode, they don't get power and thus I can't wake the PC. But if I use the bottom two ports, it works fine. A small issue, but I would like to know what is causing that. Also side note, after turning on the pc, every USB port works perfectly fine. It's just only when I turn off the PC, the issue seems to arrive. Thanks for any help!
 
May 10, 2021
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because top 2 and bottom 2 is not the same. no power, no waking the pc
Does the "34" in that "USB3_34" indicate the third and fourth USB ports? And if so what does it mean for the ports that don't have that feature? Also if I use the USB 2.0 ports on the back and the front I/O, those also get power. I would really like if you explain why those two ports aren't behaving that way?
 
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And if so what does it mean for the ports that don't have that feature? Also if I use the USB 2.0 ports on the back and the front I/O, those also get power. I would really like if you explain why those two ports aren't behaving that way?
"Ultra USB Power" is a feature on ASRock boards where the power supplied to the USB ports is from the 12V rail of the PSU converted to 5V, instead of using the 5V rail of the PSU directly. This is to prevent the voltage from dropping too far when the USB ports are experiencing heavy power draw. This is only really a concern if you have something like a smartphone that's charging and something like a 2.5" portable drive connected to the same pair of USB ports.

My guess as to why those two ports can't wake up the computer is simply because their power rails are shut off. I'm not sure why that is other than the only thing powering the computer in S3 Standby is the 5V rail (though not to be confused with the 5V_SB line, which is used when the computer is turned off to keep something alive for "soft" power ups)
 
May 10, 2021
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"Ultra USB Power" is a feature on ASRock boards where the power supplied to the USB ports is from the 12V rail of the PSU converted to 5V, instead of using the 5V rail of the PSU directly. This is to prevent the voltage from dropping too far when the USB ports are experiencing heavy power draw. This is only really a concern if you have something like a smartphone that's charging and something like a 2.5" portable drive connected to the same pair of USB ports.

My guess as to why those two ports can't wake up the computer is simply because their power rails are shut off. I'm not sure why that is other than the only thing powering the computer in S3 Standby is the 5V rail (though not to be confused with the 5V_SB line, which is used when the computer is turned off to keep something alive for "soft" power ups)
So can I really do anything about it? Like is there a fix or is it my motherboard is broken or something? And also if the power rails apparently gets shut off, then shouldn't it stay turned off even if the computer is turned on assuming there is a hardware fault there?
 
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So can I really do anything about it? Like is there a fix or is it my motherboard is broken or something? And also if the power rails apparently gets shut off, then shouldn't it stay turned off even if the computer is turned on assuming there is a hardware fault there?
There's no fix because this is how the board was designed. The purpose of the "Ultra USB Power" USB ports is for higher power USB devices that are sensitive to voltage droops (e.g, portable hard drives that are completely powered by USB)

If you want to wake up the computer using a keyboard or mouse, I suggest using the USB 2.0 ports. Keyboards and mice are USB 2.0 anyway and most computers are set up to wake from those ports.
 
May 10, 2021
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There's no fix because this is how the board was designed. The purpose of the "Ultra USB Power" USB ports is for higher power USB devices that are sensitive to voltage droops (e.g, portable hard drives that are completely powered by USB)

If you want to wake up the computer using a keyboard or mouse, I suggest using the USB 2.0 ports. Keyboards and mice are USB 2.0 anyway and most computers are set up to wake from those ports.
Thank you! So ig those 3.1 ports which aren't receiving power after turning off the system have no faults in them and they are designed to be that way?
 

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