10Mbps on 100Mbps Network

[moonlight-strider]

I have a Dell Inspiron 5676 that I recently upgraded the CPU on (R5 1400 to R5 2600) and I've noticed that the internet speed seems to be significantly reduced on this system for a reason I can't pinpoint. As to whether or not this has anything to do with the CPU upgrade, your guess is as good as mine. Specs are as follows:

AMD Ryzen 5 2600
AMD RX 570 4GB
12GB DDR4 2400MHz
2 1TB HDDs, one for boot and one for games

Here's what I've tried so far:

I have a WiFi router that my PC is plugged into via a Cat6 Ethernet cable. It's a quite new cable, but I switched the PC to the built in WiFi to see if it was something with the cable. It's not.

Regardless of whether or not this system is connected to Ethernet or WiFi, it always gets ~10mbps- far lower than it should be reading on Ookla SpeedTest. I've tested this system before and have gotten up to 80mbps as far as the download speed is concerned. Interestingly enough, the upload speed is actually the same as it's always been, around 8mbps- meaning that I'm now getting the same download speed as I am upload on this machine. This is not good because I will have to re-download games and things once I get an SSD, and I also just don't want slouchy internet when this machine was far more capable not long ago.

I have a laptop I tested, and it got ~30mpbs (it's an older one from around 2012), so it's specific to the Inspiron 5676, yet it is not the fault of either the WiFi specifically, or the Ethernet specifically. It's something else that's messing with my speeds, and I'm not sure what that is. I have no background programs open except ATI Radeon Settings Lite, Malwarebytes, and Razer Synapse.

I am using Charter Spectrum internet with a Linksys AC1200 router and an ARRIS TM902A cable modem.

[2FA]

If you check the status/properties of the NIC, is the speed of the link 1Gbps or is it 10/100 Mbps.