Inspiron 24 3464

Is 1000 Mbps the speed claimed by your ISP, or is that just the max link speed the router can communicate with the PC?  Assuming the Ethernet is connecting at its max link speed (100 Mbps), what's your actual download speed?  In other words, where's the bottleneck, between internet to router, or between router to Ethernet/PC?

You might get better performance with a USB3>10/100/1000 Ethernet dongle, assuming router>PC is the bottleneck. You'd have to disable the onboard Ethernet in BIOS setup, assuming that's an option in BIOS. Otherwise, disable it in Device Manager.

According to the specs, you should have Wi-Fi 802.11ac which supports 2.4 and 5 GHz so I don't think you'd find a faster card. You do need a dual-band router to connect to 5 GHz WiFi, which is faster than 2.4 GHz. So what frequency are you connecting WiFi to the router, and what's the router's rated link speed?

Keep in mind that while 5 GHz WiFi is faster than 2.4 GHz, its range is shorter so the router might have to be moved closer to the PC...

 There are many different types of 802.11ac wireless cards.

for example the M.2 wireless card in your Inspiron might be Dell MHK36 which is AC3165 and looks like this one

Theoretical max speed of AC3165 is 433 Mbps.  You can upgrade to newer type AC8265 M.2 WiFi card with theoretical max speed of 867 Mbps.  Other similar fast types include AC8260.

example of Dell AC8260 Dell 8XG1T

note practical speed is often much lower than theoretical due to many factors:

distance - distance from the access point, as well as any physical obstructions, such as walls, signal-blocking or reflecting materials affect signal propagation and reduce speed
interference - other wireless networks and devices in the same frequency in the same area affect performance
shared bandwidth - available bandwidth is shared between all users on the same wireless network.

PS The theoretical max speed of 802.11ac is eight 160MHz 256-QAM channels, each of which are capable of 866.7Mbps, for a total of 6,933Mbps.

Not surprised.  24 3464 spec 

8930 spec

@smr1954  Duh! I should have though of this first...

Appears Dell installed SmartByte software on this PC model. You can read this about testing SmartByte's (negative) effects on speed.

If turning SmartByte off solves the problem, IMO, just get rid of it completely, don't even bother updating it, since it's unnecessary and only causes problems...

Mt xfinity ISP does top out ay 1000mbps. I have an xfinity router plugged into a tp-link 5 port gigabit switch and off that switch I have the Inspiron 24 3464, a dell XPS 8930 and a tp-link AC1750 router plugged into it. Both computers have a direct Ethernet line running to them from the switch. The XPS runs between 750 and 900 mbps wired. the Inspiron runs at less than 100 mbps wired or wireless they are the same. I have 2 laptops that run about 150 to 250 wireless from tp-link or xfinity routers.