I have noticed that my zoom call quality has been subpar lately. In troubleshooting this, I did a speedtest, and found that I am getting 250-300 mbps on my main device, rather than the 800mbps that I pay for with Comcast Xfinity.
I called Comcast and they reported to me that everything seemed to be fine on their end, and blamed my modem. At that time (which was just 4-5 days ago), I was using a TP-Link TC-7620 (DOCSIS 3.0) modem, with a TP-Link AC1900 wifi router. I was previously getting good speeds on the modem, so I didn't think it was the modem. But the phone tech, as well as the in-person tech said it was the modem, and that replacing it would fix the issue.
I have now purchased a Netgear Nighthawk CM-1200 (DOCSIS 3.1) modem. And wouldn't you know it? It DIDN'T fix the issue! (still using the TP-Link router)
Spent a lot of time with customer service, and a second technician just left my home. Issue still persists.
The technician WAS very helpful. He had me tweak some ethernet controller settings (in particular I changed my "Speed & Duplex" from "Auto Negotiate" to "1.0 Gbps Full Duplex"). This did improve my download speeds a small amount.
When he connected his tester to my router, he showed he was able to pull in a full 950-980 Mbps through the router. So the technician concluded that it must be my device's fault.
However, ALL of my devices have the same issue: Whenever I run a speedtest with ANY of my devices (connected directly into the modem, or the router's LAN port, or via the router's wifi) with either Ookla or Xfinity speed tests, the speed starts FAST initially, showing 750-920 mbps (which is what I expect), but after 2-3 seconds, the speed begins to taper down and completes at 250-300 mbps. Sometimes lower, sometimes higher (like I just did it and got 500, but then tested again and got 220).
My PC is using a wired connection with a CAT6 cable to the router, which in turn is connected to the modem with a CAT6 cable. But even when I am hardlined into the modem with my PC, it doesn't change anything (getting the same speedtest results). Even if I have no other devices connected to the router (via wifi) the issue persists (this is ensured by turning the wifi radio off). At any one time I could have about 12 devices connected to the wifi, but only about 6-8 of those are using internet. When all the kids are home, this can increase to about 16-20 devices on the network, with tablets and smart TVs being on (and accessing internet, all via wifi). Will note here that there is only one device that uses ethernet instead of wifi and that is my main PC. However, ALL of my devices that access the internet and can run speedtest are showing the same results.
My Network:
Netgear Nighthawk CM-1200 cable modem with 4 ports (only 1 being used)
TP-Link ArcherC9 AC1900 wifi router with 4 LAN ports (only 1 being used currently during testing)
[[Disney's MyCircle ver.2 connected to the router via stock CAT cable, and wifi when fully setup (but disabled for this testing)]]
[[TP-Link AV600 Powerline Adapter (TL-PA-4010) connected via CAT6 cable to the router (but unplugged for testing)]]
[[Netgear WiFi Mesh Range Extender EX-7000 plugged into the other end of the powerline adapter (but unplugged for testing)]]
My PC:
MoBo: ASUS ROG Strix B550-F gaming
CPU: AMD Ryzen 5 5600x (no overclocking) with stock cooler
RAM: brand new G.Skill Trident Z RGB DDR4-3200 8GBx2
SSD: SK Hynix Gold P31 1TB (M.2-2280 NVME) with about 350GB of space left
(there is another SATA III SSD and two HDD in my rig, but are used for storage, and no OS services)
GPU: Gigabyte Radeon RX 5700XT 8GB Gaming OC
PSU: Enermax Revolution D.F. 850W 80+ Gold cert
WOA. Update.
I actually just discovered that my laptop has an ethernet port (it was a very narrow ethernet port, but the bottom edge of the port can spring down to fit the CAT cable...).
When I tested my laptop via WiFi right next to the router, it was pulling down 260Mbps. However! when I connected the cable, I am pulling 940-960Mbps consistently.
So...IS it my PC? How would I fix this!?
Thank you very much!
I called Comcast and they reported to me that everything seemed to be fine on their end, and blamed my modem. At that time (which was just 4-5 days ago), I was using a TP-Link TC-7620 (DOCSIS 3.0) modem, with a TP-Link AC1900 wifi router. I was previously getting good speeds on the modem, so I didn't think it was the modem. But the phone tech, as well as the in-person tech said it was the modem, and that replacing it would fix the issue.
I have now purchased a Netgear Nighthawk CM-1200 (DOCSIS 3.1) modem. And wouldn't you know it? It DIDN'T fix the issue! (still using the TP-Link router)
Spent a lot of time with customer service, and a second technician just left my home. Issue still persists.
The technician WAS very helpful. He had me tweak some ethernet controller settings (in particular I changed my "Speed & Duplex" from "Auto Negotiate" to "1.0 Gbps Full Duplex"). This did improve my download speeds a small amount.
When he connected his tester to my router, he showed he was able to pull in a full 950-980 Mbps through the router. So the technician concluded that it must be my device's fault.
However, ALL of my devices have the same issue: Whenever I run a speedtest with ANY of my devices (connected directly into the modem, or the router's LAN port, or via the router's wifi) with either Ookla or Xfinity speed tests, the speed starts FAST initially, showing 750-920 mbps (which is what I expect), but after 2-3 seconds, the speed begins to taper down and completes at 250-300 mbps. Sometimes lower, sometimes higher (like I just did it and got 500, but then tested again and got 220).
My PC is using a wired connection with a CAT6 cable to the router, which in turn is connected to the modem with a CAT6 cable. But even when I am hardlined into the modem with my PC, it doesn't change anything (getting the same speedtest results). Even if I have no other devices connected to the router (via wifi) the issue persists (this is ensured by turning the wifi radio off). At any one time I could have about 12 devices connected to the wifi, but only about 6-8 of those are using internet. When all the kids are home, this can increase to about 16-20 devices on the network, with tablets and smart TVs being on (and accessing internet, all via wifi). Will note here that there is only one device that uses ethernet instead of wifi and that is my main PC. However, ALL of my devices that access the internet and can run speedtest are showing the same results.
My Network:
Netgear Nighthawk CM-1200 cable modem with 4 ports (only 1 being used)
TP-Link ArcherC9 AC1900 wifi router with 4 LAN ports (only 1 being used currently during testing)
[[Disney's MyCircle ver.2 connected to the router via stock CAT cable, and wifi when fully setup (but disabled for this testing)]]
[[TP-Link AV600 Powerline Adapter (TL-PA-4010) connected via CAT6 cable to the router (but unplugged for testing)]]
[[Netgear WiFi Mesh Range Extender EX-7000 plugged into the other end of the powerline adapter (but unplugged for testing)]]
My PC:
MoBo: ASUS ROG Strix B550-F gaming
CPU: AMD Ryzen 5 5600x (no overclocking) with stock cooler
RAM: brand new G.Skill Trident Z RGB DDR4-3200 8GBx2
SSD: SK Hynix Gold P31 1TB (M.2-2280 NVME) with about 350GB of space left
(there is another SATA III SSD and two HDD in my rig, but are used for storage, and no OS services)
GPU: Gigabyte Radeon RX 5700XT 8GB Gaming OC
PSU: Enermax Revolution D.F. 850W 80+ Gold cert
WOA. Update.
I actually just discovered that my laptop has an ethernet port (it was a very narrow ethernet port, but the bottom edge of the port can spring down to fit the CAT cable...).
When I tested my laptop via WiFi right next to the router, it was pulling down 260Mbps. However! when I connected the cable, I am pulling 940-960Mbps consistently.
So...IS it my PC? How would I fix this!?
Thank you very much!
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