Browser loading speed has slowed since I get TMO Home Internet and don't know why.

A Windows update could have knackered up some things with the network stack... is prone to locking the receive windows and/or MTU to weird values and such.

Can go to the broadband tools section at speedguide.net to download their TCP Optimizer to reset everything quick and easy.  They may even have a link directly on the home page for it now it has become so popular.  You just right-click it to run as Administrator, pick the network card from the drop menu, and click to reset things to Windows Defaults.  It will prompt to make a backup (has a restore function as well), and then prompt you to reboot the system to apply everything.

After that, go back to speedguide.net and go to their TCP Analyzer page.  It should flag a notice about the MSS/MTU not being optimized.  Windows SHOULD be detecting and setting MTU at 1420, which is not optimal by normal standards but what is required because of their funky IPv4/v6/v4 tunnel crud they are doing (technically, you may be able to override it to 1440, but that can work against you in some network situations...1420 is the more common values used with MTU discovery).

That is important to verify, because if it is too high (ie, trying to run the usual numbers between 1460 and 1500), it can cause packets to be broken down into two smaller packets... bogging things down.

You can try clearing the browsing data say on Chrome and test after doing so. To clear out Chrome browsing data go to Settings  then search for cache. The results for the Security and Privacy window should highlight "cache". You can then use the navigational arrow to the right to use the options to clear browsing data. There are three boxes that will probably be selected in the basic option tab. If you go to advanced you can see additional options. If the slow loading is due to stale cached data then when you clear out the cache and new information is pulled in it may improve the loading. The first time a page is accessed after clearing the cache it will probably load slow but if the issue is related to stale cached information this might help. 

NOTE: Start with only the cached data and if you want limit the time to say one day. If you know you have a site you frequent and want to be selective then limit the time. If this helps consider taking it farther. 

I launched Chrome, which I seldom use now, and when it came up the default startup page rendered a bit slowly for me. I went and cleared the browsing data and then launched a new tab to go to the start page. It did render more quickly. I have seen this before but where all browsers behave the same well not so much. 

If you run a speed test with speedtest.net it should provide up and download values and latency for the communication to the server. The latency value would be good to know. If latency is less than 60 ms that is positive. Jitter less than 10 ms also should be ok. If there is loss what the % is would reflect on performance. 

If there is loss then another important bit of data to look at is in the router web interface. Web into the 192.168.12.1 interface and record the data on the "internet Connection" for the Primary and Secondary signals. If the SNR, signal to noise ratio is poor that would suggest noise so performance would suffer as retransmissions of packets would take place. The result would reflect what you see in browser load times. All the values in this data would be helpful to know to rule out the signal or point to an issue in the cellular signaling. If the problem is not due to the cellular signaling then it would be necessary to back into an investigation of the local wireless or wired connection by the client.

In effect I am trying to recommend doing that which is simple and easy first. To trouble shoot performance issues it is necessary to start at the bottom and work up and not jump into more complex pieces of the puzzle. There could be a number of reasons for slow load times for pages. An online search can result in a significant amount of information about this but well that might be slow. :-) 

Depending upon the signal you have for 4G LTE and 5G NR signals it could be a major datapoint to know. If you only get 100 Mb down with an n41 5G LTE secondary signal then it could be in part due to the SNR being poor which can suggest packet loss/damage resulting in poor performance. The n41 5G signal can do much better than 100 Mb down. If there is vendor traffic throttling well this might account for the speed being only where it is. The key though is to know if there is a strong clean signal with low signal to noise ratio. If there is noise the performance will suffer. Working on trying to improve the signal quality to have better SNR would help with performance.

thanks! I'll do the cache thing later today. Honestly, I don't think that's it. I was using ATT internet before TMO and that was fine. The day I started using TMO (which, btw I like a LOT better) is when the issue started. I notice, however, it's only doing this "slow loading" with my home PC, not my laptop. It's hard to describe, it's more of a "freezing while loading" instead of "slow loading". When I open up a new tab, I get the spinning wheel in the tab, then it stops for about 3-5 seconds, then continues. Then, when I'm on a page and start to scroll down, I get the freezing thing again.  It happens with all browsers, just with the PC. I never use Edge, and it does it with Edge as well, so that leads me to believe it's not a cache thing. I checked the speeds again, the PING is consistently between 30-35, which is lower than it was with ATT. It has to be something between TMO and the PC as my laptop and phone have zero issues.  ¡Gracias!  

In that case some things to look at: 

• If it is Windows 10, check to be sure there is not an update pending. 
• If W10 reboot it and see if it changes the equation.
• A likely culprit with W10 and the desktop could be a network card driver. (I will assume wireless.) Check for an updated NIC driver and install a new one.
• If it is an older PC maybe the wireless NIC driver is having issues.
• If your PC is close to the router and you can use an Ethernet cable try that instead of wireless.
• If it is W10 open a command window and enter “netstat -e” (no quotes) Look for errors.
• Además netstat -s for protocol statistics. Look a % of errors etc.. to actual connections.

Look at the web interface on the router "Statistics" for the various wireless bands for "Discarded Received Packets". If the PC NIC is not working well it might be error prone. 

If you are familiar with Linux and have or can make a bootable USB drive download say Linux Mint and make a live USB stick to boot from and confirm results with Linux vs W10. I only suggest Mint as it is very simple to use and so similar to Windows for navigation. My experience is that when I boot up with Linux Mint or most Linux distros the wireless is usually detected and it is pretty quick and easy to join the wireless network. If the wireless NIC is a Realtec the probability is good it would work fine. 

Again, thanks! You’re talking a lot of “nerdy” stuff to me, but I’ll see what I can do.

It is wired directly to the router via ethernet. I even changed cables and put the router closer to the pc. It was about 20 feet away, now it's about 4 feet. (yes, brand new cables both times) 

With my laptop, which is wireless, I do not experience these issues.

I know nothing about Linux and have no idea how to do what you asked. Lo sentimos.

It's a strange one, but I know it can be solved by someone. I can't be the only one this has ever happened to.

I’ll buy a case of beer for anyone who can help me solve this issue!  lol

OK sorry. Networking issues often do require getting nerdy at times. It does appear to be a client issue. A bad network card or driver are pretty much the first places to attack. If you have more questions just post them here. If you have some data from the reporting I could take a look at it and see what clues may be there. Windows system logs can be another place to look but if you are not familiar with the tech side of things that could be a bag of snakes. 

It worked before. It can probably be made to work again. It might just take a bit of effort.

Oh, I appreciate the info you've provided and I will do what I can with it and can't thank you enough. It's just frustrating is all. It's got to be something my PC doesn't like with the TMO home internet. I plan on testing a something later today. I'll use my hotspot on my phone, hard wire it to my PC, unplug the TMO and see if the freezing issue is still there. I'll report what happens. Thank you for everything!

I have the same PROBLEM of VERY EXTRA LONG TIME (60-120 sec)  with loading the new page since I switched to TMHI even though we have 4 bars (3700 feet ± from the nearest tower)

1-Then I reconnected our existing router (tp-Link) through the T-M Gateway, and opening the page goes back to “normal”  around 2-3 sec. WHY?

2-Listen to music from Youtube through home audio sytem wirelessly connect from the T-M Gateway WILL GIVE “STATIC/LTTLE RATTLE” eventhogh we got 4 bars (80-90 mb). However if we connect CAT6 cable from our labtop to T-M Gateway, the "Static Noice/Skipping/Rattle " will be gone. WHY?

3-Our wireless printer could not work with T-Mobile Gatewat like we used to do with our existing router (tp-Link), WHY?

Did I connect wrongly, miss something, or just that is just the way T-M Home Internet Gateway work ?

Gracias,

Due to loosing the wireless function/ transmit signals  (only works with ethernet = cable,) tommorrow I have to take the TMHI Gateway to the store nearby to have it replaced with either new SIM card or the whole thing as the TM-Tech online recommended… Did I make a wrong choice with TMHI?

The problems may be with the wireless radios for the local WIFI delivery. When you use the TP link and or the Ethernet wired connection you are bypassing the T-Mobile local wireless. The cellular uplink connection appears to be working. From your descriptions it could well be your gateway is not running the wireless radios properly. 
If your printer is older it may require you to make a separate 2.4 ghz network to get it to connect with your gateway. Discuss this with them as well. Some older wireless network adapters don't work well with the newer WiFi 6 operation of the THI gateway. There are multiple conversations in the community regarding getting printers to connect. The authentication type for the printer may also demand attention. Make sure the 2.4 ghz SSID also provides the proper authentication type the printer uses.