My Acer Nitro 5 AN515-57 has extremely slow Wi-Fi downloads even though uploads work normally. On the same 5 GHz network, my phone reaches roughly 280–380 Mbps download, while the laptop gets only about 4–5 Mbps down and 60 Mbps up.
The laptop uses a Killer/Intel Wi-Fi 6 AX1650i adapter. Its connection status shows a strong signal of 90% with an RSSI of -46 dBm, but the receive rate is exactly 6.5 Mbps while the transmit rate is 156 Mbps. It is connected on 5 GHz, channel 149, using 802.11ac.
I have already tried updating the adapter from the original Intel driver version 22.40.0.7 to Acer's version 22.130.0.5, but the receive rate did not change. I also checked the adapter settings, including 5 GHz preferred band, automatic 5 GHz channel width, no SMPS, maximum transmit power, enabled throughput booster, disabled U-APSD, and 802.11ax mode.
What could cause such a low receive rate despite the strong signal and normal transmit rate? Could this be a Windows or Killer driver problem, a router compatibility issue, or a loose antenna or failing Wi-Fi card? What should I test next?
2 Answers
Install the latest driver directly from Intel’s support package for the AX1650i, then remove the existing adapter in Device Manager and install it cleanly if a normal update does not make a difference. Since the latest driver was already tried without improvement, the next useful comparison is a Linux live USB or another access point. That will help distinguish a Windows driver issue from an antenna, card, or router-compatibility problem.
Try installing the newest Intel/Killer driver available rather than relying only on the older Acer package. If that does not help, boot the laptop from a temporary Linux USB and test the connection there. If download speeds are normal in Linux, the hardware is probably fine and the issue is likely Windows or its driver configuration.
If the problem happens in Linux too, power the laptop down and reseat the Wi-Fi card. Also check that both tiny antenna connectors are firmly attached. A loose connector or damaged antenna cable can cause one-way performance problems, although a failing card is less common.
A loose antenna connector is worth checking too—the connector can come partly loose even when the card itself is seated properly.