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Troubleshoting slow internet - Router? Cable modem? or my ethernet Adapter?

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Troubleshoting slow internet - Router? Cable modem? or my ethernet Adapter?

I recently upgraded from a Netgear AC1200 to Netgear AC1750 R6400v2. I also upgraded my cable modem from a Zoom 343 speed to the Surfboard 6183 which is twice as fast and twice as many channels. Upgraded my internet speed to 250 Mbps d/l.

I've had really poor wifi speed since doing these things. I've messed with the router settings some, with no help. I have had decent speeds on my desktop Gigabit ethernet connection but not as good as I'd expect.

I plugged into the cable modem directly with my Gigabit ethernet and did and got 235 to 290 d/l on 4 tests. Upload was fine.

Then I was certain it was the router, and I've already got an RMA to return it because of the above test. 

But - today I plugged into modem again, and got great speed tests, but when I went into Chrome, I had timeouts on almost every site I tried to enter. That's why I put Adapter in the subject. I've heard so many different things on how your settings should be on an ethernet adapter.

I've cleared my cache and history and only had 4 tabs open. Closed and reopened Chrome. Same thing.

So, since speeds are great, what do you guys think? I don't want to ship this 4 month old router to Netgear and get a Used Refurbished router in return if it's something with the modem. Please help. I've spent a small fortuen upgrading router, modem and internet and haven't gained a thing.

BTW, I only have 5 wireless devices and my desktop ethernet. That shouldn't be bogging down a 1750 dual band router! with 250 Mbps internet speed. 

All of my wireless devices are 802.11ac except my tablet, it's 802.11n.

Surely all of my wifi devices don't have bad adapters. And my router is setup so it's no more than 20 - 25 feet from any wireless device. Desktop is 2 feet from router. 

My AC1750 Router is packed and I'm about to take to UPS, but when this terrible lag and timeout issue on Chrome started, I got concerned.

Sorry so long, but I wanted to cover everything that's been done.

Thanks for ANY... Help



Re: Troubleshoting slow internet - Router? Cable modem? or my ethernet Adapter?

One would think you should be getting good speeds with that setup. 

Things I would try. 


Check your cable connections to see if any are loose including where it connects to your house and any splitters.

If you have spiltters, try removing them for testing.

Sign on to the modem and see if the levels are in spec. 

Power down that 802.11n device as I have read some routers slow to the slowest device. 

Try testing with a different computer is one is available. 

Try a different browser on your computer.


Hope this helps.