Question Ping/latency spikes seemingly out of nowhere on ethernet


Jul 15, 2012
Hello, around January 1st, I have noticed during online gaming sessions that I would occasionally, and sometimes frequently, get ping spikes for a few seconds when before going back to normal. For example, in League of Legends, I would get around 17ms-18ms at all times, while now it fluctuates between 17ms-30ms and in a few minutes get hit by high ping anywhere between 50ms-150ms for a few seconds. In other games that are very sensitive to packet loss, it's very noticeable and almost unplayable.

I don't remember doing or installing/changing anything that may have introduced this issue.

Here are my downstream/upstream signal levels: View:

I pinged and, normally and in safe mode, and the ping would fluctuate anywhere between 9ms to 35ms on average while sometimes getting up to 100ms-150ms request timed out (and even "general failure"? sometimes), pretty much exactly like how I've noticed it while playing games. Packet loss seemed to average around 2%-6% before and after changing things that I listed below, but I don't think these small variances had anything to do with those changes.

I have Windows 10 version 20H2, Xfinity with 1Gbps/down and 40mbps/up (my download and upload speeds are completely fine), have a Netgear CM1000 modem and Netgear R7800 router (I never had QoS enabled). I have tried almost everything under the sun that I can think of, which I will attempt to put here:
Power cycled both modem and router for 15 seconds and again for 15 minutes
Restarted modem through Xfinity Assistant
Tightened coax connection on modem and outside
Factory reset both modem and router
Plugged modem and router directly to outlet instead of surge protector
Dusted modem and router
Chatted with Xfinity customer support, and they weren't able to see anything wrong, signals looked good and offered a tech visit, but held off as to see if I can't resolve the issue on my own
Changed ethernet cables connecting modem to router and router to desktop (they were both either some form of Cat5 or Cat6, don't really remember but download and upload stayed exactly the same)
Enabled/disabled IPv6
Changed DNS to Cloudflare and GoogleDNS
Tinkered with ethernet controller advanced settings, such as disabling offload settings, disabling eco settings, changing receive/transmit buffers to lowest/highest settings, speed/duplex, and the other settings as well
I have a Z490 board and I was heavily convinced it might be an issue with the I225-V chipset, so I installed a Realtek NIC to test that theory, but it didn't seem to be the case
Tested wireless on desktop, but similar/worse ping fluctuations occurred
Plugged my modem directly into my desktop to see if it could be a router issue, but playing games and doing ping tests showed similar fluctuations, including timed out requests followed by high ping. I even tested using my laptop using an ethernet adapter, first connected through router, then just the modem, but ended up with similar results
I probably did many other things that I don't remember off the top of my head, but I don't believe they were super significant. At this point, I have a feeling it's an issue regarding a possible faulty modem. It could even be ISP related, or cabling issue, but my signal levels do seem good, so would that really be possible? I sadly don't have a spare modem to test this but if there is no other reasonable culprit, I can try ordering another CM1000 or similar/better 1Gbps modem and just return it if my issues persist. I'm up for any suggestions. Thanks!
The latency is not that bad, a few spikes here and there of a extra 100ms will not have much effect.

The packet loss is a huge issues. Even 1% is a massive amount to lose. You will always see packet loss here and there but is will be a almost unmeasurable percentage.

It sounds like your ISP connection. When you talk to the ISP only talk to them about packet loss not the latency. The packet loss they will fix, latency is generally load related so if it just that they will blame everything except their network.

I would check the numbers in the modem to make sure the levels are withing the recommended ranges. It varies a little bit based on the type of docsis you are using and it would be messy to post the tables here.

Your first step is to run tracert to get the IP of the first ISP router. It is generally hop 2 when you only have 1 router in your house.

You want to leave constant ping run to hop 1 (your router) hop 2 (the ISP router) and then some final ip like

Your goal is to show the ISP that you have no loss at all to hop 1. This means that your router and pc are not the problem. You want to show them that you see issues to their router and it has a actual impact on your traffic because it also affects

If it is in the ISP connection to your house this is actually the easiest to get fixed. They have many tools to find why you are getting packet loss in this part. If the problem is farther into the network it get much harder to get the ISP to do some cases it might not even be in their network.

..................the signal level thing did not load the first time I looked at it. Your levels look fine. This means it is not a simple modem or cabling issues.