Maybe this is a post better made in the Nvidia forums, but I figured I'd leave one here just in case.  I pretty much built a new computer around my evga 3080 ftw3 with an MSI z490 meg ace motherboard, and for months now I thought there were problems with the motherboard's USB, which I even ended up RMA-ing.  The new board fared no better than the old one.  Then this week I started reading about problems with the 3000 series cards in conjunction with AMD cpu's/motherboards causing exactly the kind of problems I've been having, which begged the question, is there a similar problem happening with intel-based systems, even if it's less widespread.  I've found some threads that seem to indicate this might in fact be the case.  Whether the responsibility lies with nvidia, cpu manufacturers, or motherboard manufacturers (or some combination of all three) is unclear to me, at least for intel based systems.  AMD has always had its issues with drivers and such.
 
So I'm wondering if anyone here with an intel system is having USB problems after installing a 3000 series card.

Outofstock4ever
That's just a issue with 500 series motherboards on AMD. I don't think it has nothing to do with your problem.

Thanks for the response.  I guess it's back to the drawing board then.  The usb devices themselves work fine in a different pc, but so far I've been through two MSI z490 meg aces that have this problem.  I figured it's unlikely that they'd both have the same problem so was hoping to zero in on a different solution, which I thought might be the gpu.  I don't see any threads about this generally being a problem with that model motherboard, either.  I guess it's possible the replacement they sent me just has the same problem, even if it's unlikely.

Have you checked to see if your BIOS is up to date?

Do you have another GPU you can try in that system as well?

EVGATech_LeeM
This may be relevant: 

I just installed the 'fix' 1.2.0.2 and it solved NONE of the USB  or audio issues.

At least it seems like the motherboard and not the GPU as the source. It might not be the most useful information but at least you can look up information for less causes then trying to combine the two.

Ciddharthas
Maybe this is a post better made in the Nvidia forums, but I figured I'd leave one here just in case.  I pretty much built a new computer around my evga 3080 ftw3 with an MSI z490 meg ace motherboard, and for months now I thought there were problems with the motherboard's USB, which I even ended up RMA-ing.  The new board fared no better than the old one.  Then this week I started reading about problems with the 3000 series cards in conjunction with AMD cpu's/motherboards causing exactly the kind of problems I've been having, which begged the question, is there a similar problem happening with intel-based systems, even if it's less widespread.  I've found some threads that seem to indicate this might in fact be the case.  Whether the responsibility lies with nvidia, cpu manufacturers, or motherboard manufacturers (or some combination of all three) is unclear to me, at least for intel based systems.  AMD has always had its issues with drivers and such.
 
So I'm wondering if anyone here with an intel system is having USB problems after installing a 3000 series card.

From what I've heard, AMD-based motherboards were having issues with USB connectivity and this was supposedly resolved by updating the BIOS on the motherboard.