Need some networking help.

[Punisher]

I am trying to figure out what's going on.
1. If I connect via Ethernet directly to my cable modem I get just about 1 gb up and down.
2. If I connect to the modem's WiFi I get about 400gbps up and down give or take.
3. I have a separate TPLINJK Router with 5ghz WiFi. It is connected to the modem via Ethernet cat 5
4. I have a brand new laptop with WiFi 6e
5. Both the cable modem and the old and new router are within about 4 feet of each other and the laptop

If I connect to the TPLINK WiFi I get about 500 up and down give or take.
If I connect to the TPLINK via Ethernet I get about the same.
I picked up a new router at Microcenter. ASUS AXE7800 Tri-Band RT-AXE7800
Set up the new ASUS router via Ethernet. Tried using the 2.4GB and the 1GB WAN ports. No difference in results on Ethernet. Maybe a little more but never even reached 600mbps. Unplugged the old router completely which brought the whole house down but wanted to see if anything was interfering.
Wifi did go up to about 700-750 give or take, but Ethernet was still struggling to hit 600. It was slower than the WiFi.
The salesperson said that the WiFi on the cable modem might be interfering so I turned it off. No changes.
No change on Ethernet.
I'd like to get my 1 GB via Ethernet and WiFi without connecting to the cable modem because everything in my house is on the router and I need to access files across the network. Can't do that when I'm on the cable modem ethernet.

[Blackhawk]

Super non-expert, but some thoughts, and a big caveat that I am, likely as not, wrong, but am hoping to offer some breadcrumbs. And that's assuming that I am correctly following what you're asking (a concern of my comprehension, not your presentation.)

First, these speeds, are they coming from file transfers within the network (copying files, etc), or from the internet? If the latter, you may never get what the hardware is capable of if the source isn't able to feed it at that speed.

If I connect via Ethernet directly to my cable modem I get just about 1 gb up and down.

That sounds correct.

Tried using the 2.4GB and the 1GB WAN ports. No difference in results on Ethernet. Maybe a little more but never even reached 600mbps.

I don't believe 2.4Ghz wifi is capable of full gigabit speed. I believe that the fastest 2.4GHz caps out at 600Mbps under ideal conditions (anything from the neighbor's microwave to the people across the street having a close channel can reduce this.) 5Ghz is faster, but is more susceptible to interference over distance. And again, that's all assuming that every piece of the puzzle is the latest standards and that everything has ideal conditions (hint: they don't have ideal conditions - ever - in the real world.)

If you go into settings / Network and Internet / Ethernet and click your adapter, what's it show for the speed at the bottom?



Also, if you have one, try different cables. Old cables/cheap cables/damaged cables can offer reduced speed.

[Punisher]

some clarifications.
1. I'm using the Speedtest app AND the online speedtest through Optimum, my provider.

2. The " the 2.4GB and the 1GB WAN ports" are both Ethernet ports. The router has 2 different WAN Ethernet ports a 1GB one and a 2.5GB one. I tried both ports while plugged into the routers 1GB LAN port with the laptop. That is the 500-600mbps I got via Ethernet vs getting almost 1GB via Ethernet directly on the cable modem.

3. Laptop shows 1GB when connected via Ethernet. Both on cable modem and on router.

I bought a brand new Cat 6 Ethernet to try. Thats what Ive been testing on.

[Kasey Chang]

If you go through a different router you'll just have to accept a bit more overhead.

Your cable modem doesn't speak 2.5Gb so it's talking 1Gb with the new AX router.

IMHO, if you want full Wifi 6E speed, you need an external adapter from the same maker as the new wifi router, for your laptop, even though it claims to do Wifi 6E. In my experience, different people's 6E don't necessarily work together and just falls back to wifi 6.

I know they are all SUPPOSED to work together.

Your cable modem should have 2 Ethernet ports for connecting stuff. Use one for your own hardline, the other for the AX router.

[Punisher]

Honestly, I'm more concerned with the major drop in Ethernet speeds. In fact, with the new router, the WiFi is somehow a bit faster than Ethernet on the same router. I know I forgot a lot of IT, but that is just not making sense to me.
Even if I put the modem 1GB LAN onto the router 1GB LAN, I would this that I should be seeing at least close to the same speeds as directly on the modem.

[Kasey Chang]

You can check if all the ports are full duplex?

[Punisher]

You can check if all the ports are full duplex?

Thanks for the help, although indirectly...
I didn't know how/where to check this so I Googled it for my old router. that didn't actually come up with any results towards the top but what did come up with my exact issue. The ethernet connection was giving me about half of the cable modems speeds.
Turns out that there were 2 things I needed to change.
The 1st one had me scratching my head as to why there was even such an option.
Apparently, the old router has a thing where it does a speed test when originally set up and limits your speed to that. Rebooting doesn't seem to make it redetect. I had to go in and just change the WAN port to a manual 1000 up and down. I STILL don't even understand why this is a thing. What if someone tests during a slow outage or something? Why have this auto set at all? Just always set the router to the max speed it can support and call it a day. Then if you have slow Internet one day and super fast the next there is nothing limiting you.

The second was similar and to be honest, I'm not sure if I needed to do that or just the above. There is a setting to auto detect the negotiation speed on the WAN port. It doesn't actually tell you the negotiated speed but I changed it from auto to manual and set it to 100 up and down as well.

I am probably going to retest the new modem as well to see if it has the same issue and if so change it and see if I get better speeds with Ethernet and WiFi. If so, I'm gonna keep it, my old one is probably 4-5 years old but working but if the new one gets me better speed for both it will be worth it. I suspect that this may also be why my TV sometimes lags when streaming.
If I can't fix the issue on the new one then I'll just return it.