[SOLVED] Incredibly low 5g wifi speed?

[drumtitan]

I have a Asus rog GT AC2900. I had a splitter go bad that was put in by the ISP. They came out and fixed it and my 1 gig internet is back to normal. The problem now is that after I leave the living room of my apartment my wifi speed goes from maxed out on whatever device I run a speedtest on, to less than 30Mbps. I thought it had something to do with signal but when I changed the channel or messed with any setting and applied it I would get normal speed from all the rooms in the apartment for 20 minutes and then it would go back to 30Mbps. The even odder part is that router that I am given through the ISP works fine. I would use that one but it loses a lot of speed compared to what I was getting from the other router so I would rather figure out what is wrong with the AC2900 and use that than the default one.

 

[drumtitan]

my drivers are up to date. I have factory reset it. I have tested almost every device that is in the apartment. I also live in a rather small apartment, about 1200sq ft or less.

 

[kanewolf]

I have a Asus rog GT AC2900. I had a splitter go bad that was put in by the ISP. They came out and fixed it and my 1 gig internet is back to normal. The problem now is that after I leave the living room of my apartment my wifi speed goes from maxed out on whatever device I run a speedtest on, to less than 30Mbps. I thought it had something to do with signal but when I changed the channel or messed with any setting and applied it I would get normal speed from all the rooms in the apartment for 20 minutes and then it would go back to 30Mbps. The even odder part is that router that I am given through the ISP works fine. I would use that one but it loses a lot of speed compared to what I was getting from the other router so I would rather figure out what is wrong with the AC2900 and use that than the default one.

These "gaming" routers try to prioritize some traffic. I don't have one of these, but if you have gigabit WAN service, you probably want to DISABLE all the smart features of the router. You want it to be as dumb as possible. NO QOS. NO prioritization.
BUT, it may just be too much WIFI interference from neighbors. Your device/router are dropping from 5Ghz to 2.4Ghz. If you have different SSID names, you can test that theory.