The other day I tried 10m for the first time working FT8 and noticed every time I was Tx my shack/gaming PC loses all network connectivity, it's cabled to a 5port switch that sits behind it, which is fed from a 15ft patch cable to the nearest jack.  Switch also feeds a multifunction printer.  At this point I don't know if the switch is being affected and therefore affecting the PC, or if it's just the PC, haven't done thorough testing yet.

I also noticed when working 20m that my Xbox One X on the other side of this room loses all network connectivity, it is wired as well directly to the jack on the wall below it.  I don't think I had this problem with my Xbox One S that was in that same spot about 4 months ago, that I can recall.

The PC is right next to my 'shack' since they share a big L-shaped desk.  The Xbox One X is 20+ feet away.  My HF antenna is a 36' end fed with 30' counterpoise, strung horizontally throughout the attic...single-story ranch style home so the antenna is pretty close to all these electronics.  I also have generously applied clip-on ferrite to all my shack cabling/wires.  I keep my FT-450D/Signalink Tx output at about 50w.

The obvious answer is probably getting the antenna out of the attic, but I'm limited to using that until I can snag a local tower someone is trying to get rid of since I have no trees on my property.

In the meantime, I'm at a loss trying to figure out why those two specific devices are affected when I Tx on those specific bands and if there is some quick fix I can use to get me by until I can put an antenna outside farther away from the xbox/pc(assuming that is my problem).  Both are important devices because the PC is how I work digital and do my 8-5 job, and the Xbox is what keeps my fiancee occupied(streaming apps) while I'm playing on the radio.

Answered in your email. You have a bit of Stray RFI, a ground would never hurt, some ferrite on everything, and the DXE-ISO-plus as a filter on your ethernet lines.

Ferrite cores, the RF Band Aid.

Type 31 material is what you want.

https://www.mouser.com/Passive-Components/EMI-Filters-EMI-Suppression/Ferrites/Ferrite-Clamp-On-Cores/_/N-bw7t7?P=1yxgx6i

ground.

and as many wraps as you can:

I dug up my big ferrite clips and did 6 wraps(two clips) on the coax drop from the attic antenna where it connects to the back of my tuner, also did the same for the xbox one x on its network patch cable where it connects at the back of the xbox.  No ferrite on jumper between tuner and swr/wattmeter.  There is four wraps on the jumper between the swr/wattmeter and radio.  Also have 2 wraps on each device power cable.

Still killing xbox network connectivity when transmitting 50w on 20m FT8.  Switched the xbox over to wireless(5GHz AP is on the ceiling about 6ft away from it), issue still happens.  I guess this narrows it down to some component inside my xbox one x that is probably unshielded and susceptible to RF interference around 14mhz?  My boys xbox in their room doesn't have this issue, and it's only another 10-15ft further away from the radio.  Other than distance, the only other difference with their xbox is that it is an S model and doesn't seem to suffer from the same problem(it used to be the one in this room before I upgraded to the X model).  No other wired or wireless devices affected.

Lowered RF Power on my FT-450D down to 30w, only got a single timeout on my pingtest to the xbox during a test TX.  Lowered to 25w, no packet loss.  So it looks like 30w~ or higher affects the xbox.

Now that we know the interference isn't affecting the network but rather the device's ability to stay connected to the network(wired or wireless), what should I try next?

My shack is plugged in to an APC Back-UPS 1500(BR1500MS) and the antenna is in the attic, so I have no additional grounding or lightning arrests on my setup.  The house electrical system is good and properly grounded, built in '99.

So I ended up doing more testing and I don't know what changed but now when I TX at 50w on 20m I can't ping any devices on my network from my PC(pingtests to router, AP, and both xboxes on wireless).  Weird, because this specific issue only happened when TXing on 10m and now it's occurring on 20m.

Did 8 wraps(4 on each end) on the 5ft patch cable connecting my shack/gaming PC to the 5port switch sitting next to it.  Tested, no packet loss to any of the four devices.  Put the xbox back on wired network, tested, packet loss to the xbox.  Put the xbox back on wireless, tested, no packet loss to any devices from PC.  Switched to 10m and tested, packet loss from PC to all four devices so TXing on 10m still kills network connectivity on my PC.

So doing 8 wraps on the PC's network patch cable to the nearby 5port switch and having the xbox one x on wireless is a solution for 20m which was my primary issue since I work that band the most, and my second most worked band is 40m which doesn't cause any issues that I'm aware of so I'm good for now.  Eventually I'll make or buy STP patch cables for everything and order legit ferrite loops.

I would guess that you have a wire that is resonant on 10m and 20m that is back feeding from your shield on your coax, the harmonics from 20m to 10m are very close together.

Maybe a line isolator at the feedpoint on your coax? This is part of the reason that many end fed antenna's require a direct ground at the feedpoint.

Just be sure that only one side of the STP is grounded otherwise you make ground loops and Ethernet does not like ground loops.  It also makes it MORE susceptible to magnetic flux interference.

When I design network installations, the patch side is the grounded side since it's far easier to bring everything to a common good ground at one location.

I haven't grounded anything, only wanting STP for the added shielding under the insulator assuming it would help in my specific situation.

Duh, you can't play games and ham radio at the same time.

Do one or the other.

If you don't ground one side then you have a free floating metal antenna wrapped around your network transmission lines.  This is worse then no shielding.

I forgot to ask, has the difference between an RF ground and an electrical ground came up in any discussions?

http://www.arrl.org/grounding

http://www.radioworks.com/nbgnd.html

I went way overboard on grounding when I set up my station and do not have any RF issues.  I'm running 1000 watts on all bands.

50 watts is nothing with good grounding so if you're having issues you should look at completely revisiting your rf grounding.  If you don't understand it there are a ton of good resources out there.  Also remember that RF grounds work best with copper strips not copper wire.  I'm using 2" wide copper for my RF grounds.  you may have decent luck with some thicker ground wire.  It's going to take some thought but you will have a much better station when you're done.