the 2.4ghz wifi on my ax73 is super slow but the 5ghz is fine, what gives

Diagnosis

The performance gap between your 2.4GHz and 5GHz bands on the Archer AX73 is typically caused by "spectral congestion." The 2.4GHz band operates on a much narrower frequency range and is shared by not only other WiFi routers but also Bluetooth devices, microwave ovens, baby monitors, and Zigbee smart home hubs. Because the AX73 is a high-gain WiFi 6 router, it can actually "hear" more interference from distant neighbors than older routers, leading to high packet loss and forced down-clocking of speeds to maintain a stable connection. Furthermore, the AX73 often ships with "Smart Connect" enabled and the 2.4GHz channel width set to "Auto" or "20/40MHz." When the router attempts to use 40MHz in a crowded environment, it overlaps with multiple adjacent channels, creating massive "co-channel interference." This forces the router to constantly re-transmit data packets, which manifests as sluggish speeds, high latency, and the feeling that the internet is "hanging" despite a full signal bar. You can confirm this by running a speed test on a 2.4GHz device and noticing a high "Ping" or "Jitter" value compared to the 5GHz band.

How to Fix It

To stabilize the 2.4GHz band and maximize its available throughput, you must move away from automatic settings and lock the router into a clean, non-overlapping channel.

1. Open a web browser and navigate to tplinkwifi.net or 192.168.0.1. Log in with your administrative credentials.
2. Navigate to the Advanced tab located in the top navigation menu.
3. On the left-hand sidebar, select Wireless and then Wireless Settings.
4. Locate the 2.4GHz section. First, find the Channel Width dropdown menu. Change this from "Auto" or "20/40MHz" to strictly 20MHz. While 40MHz theoretically offers more speed, it is unstable in 90% of residential environments and causes the slowness you are experiencing.
5. Find the Channel dropdown. Do not leave this on "Auto." Manually select either 1, 6, or 11. These are the only three non-overlapping channels in the 2.4GHz spectrum. Test each one individually to see which provides the lowest latency.
6. Scroll down to Mode and ensure it is set to 802.11ax (WiFi 6) to take advantage of the AX73's OFDMA capabilities, which help manage multiple devices more efficiently.
7. Click Save at the bottom of the page and restart the router to clear the cache and apply the new frequency map.

If That Didn't Work

• Disable Smart Connect: Go to Advanced > Wireless > Wireless Settings and toggle Smart Connect to OFF. This separates the 2.4GHz and 5GHz bands into two different SSIDs (e.g., "Home_WiFi" and "Home_WiFi_5G"). This prevents the router from incorrectly pushing a 5GHz-capable device onto the slower 2.4GHz band.
• Adjust Airtime Fairness: In the Advanced Wireless settings, locate the Airtime Fairness toggle. If you have a mix of very old legacy devices (802.11g/n) and new WiFi 6 devices, turn this ON. This prevents a slow, old device from "hogging" the airtime and slowing down the entire 2.4GHz radio.
• Change the Control Channel: If channels 1, 6, and 11 are all congested, try channel 3 or 9. While these overlap, in some rare high-density apartment complexes, they can occasionally be "quieter" than the standard three.
• Update Firmware: Navigate to Advanced > System > Firmware Update. Check for updates. TP-Link frequently releases stability patches for the AX73 that specifically optimize the 2.4GHz radio's handling of interference.

Heads Up

• Physical Placement: Keep the AX73 at least 3 feet away from other electronic devices, especially cordless phone bases and microwave ovens, as these emit radiation on the exact same frequency as the 2.4GHz band.
• Antenna Orientation: For the AX73, the four external antennas should be positioned vertically (pointing straight up) for the best 2.4GHz propagation across a flat floor plan.
• Device Limitations: Remember that 2.4GHz is designed for range and penetration, not speed. Even in a perfect vacuum, you will never achieve the same speeds as the 5GHz band due to the physical limitations of the frequency.
• IoT Separation: Use the 2.4GHz band exclusively for smart home devices (bulbs, plugs, switches) and move all high-bandwidth devices (phones, laptops, consoles) to the 5GHz band.