Stuck at 10 Mbps: How a Realtek RTL8822CE Got Trapped in WiFi 4 and What Finally Freed It

The Setup

There is a small Beelink Mini S sitting in our home that I almost never touch. My wife is the one who actually uses it day to day, so it lives in her corner and I only think about it when something breaks. It has a Realtek RTL8822CE inside, which is a 2x2 802.11ac card. WiFi 5. On paper that is plenty for everything we do, so I never gave the network side a second thought.

That assumption is exactly what let this problem hide for so long.

For context, my home connection is a 200 Mbps plan, and everything else in the house happily makes use of it. So when my wife complained that the internet on the mini PC was unbearably slow, it stood out. Not a little slow. Slow enough that a normal page load felt like dial-up. My first instinct was the usual suspects: the router, the ISP, maybe congestion. But those would have hit every device in the house, and everything else felt fine.

This is the story of how a card that was supposed to do WiFi 5 quietly settled into WiFi 4 on the narrowest possible channel, and how neither the stock driver nor the official OEM driver could pull it back out.

The Numbers Did Not Add Up

Before touching anything, I wanted real numbers instead of a vibe. So I ran speed tests across the devices I trust.

• Mac mini M4, over wired LAN: 210+ Mbps
• MacBook, over WiFi: 180+ Mbps
• iPhone, over WiFi: 170+ Mbps
• Beelink Mini S: 5+ Mbps, and only rarely creeping up toward 10 Mbps

Same house, same 200 Mbps plan, same 5 GHz network for everything wireless. My other machines were pulling 20x to 30x what the mini PC managed, and even the phone on WiFi was leaving it in the dust. That immediately ruled out the ISP and the router. The problem was local to that one machine, and specifically to how its WiFi card was talking to the network.

The Real Problem: Trapped in WiFi 4 at 20 MHz

When I opened the adapter details on the mini PC, the picture got strange. The card was connected to the 5 GHz band, which is what you want. But the reported mode was WiFi 4, not WiFi 5. And the aggregated link speed was pinned at 72 Mbps, occasionally creeping up to 86 Mbps.

That link speed is the tell. A 2x2 802.11ac card on an 80 MHz channel should be negotiating link rates in the hundreds of Mbps. A number like 72 Mbps is what you see when the card has fallen back to 802.11n behavior on a 20 MHz wide channel. So the hardware was capable of WiFi 5, it was sitting on a 5 GHz network that supports the wider channels, and yet it had locked itself into the slowest, narrowest configuration available.

Once the link rate is capped that low, real throughput of 10 Mbps is not surprising at all. The negotiated ceiling was the bottleneck, and everything downstream just inherited it.

Wrong Theory: Just Reinstall the Driver

The obvious move was to force the card into 802.11ac mode. So I went into Device Manager and started digging through the adapter’s advanced properties, looking for the usual knobs: a wireless mode selector, a channel width setting for the 5 GHz band, anything that would let me push it to AC and 80 MHz by hand.

There was nothing. No mode option, no bandwidth override. The properties that would normally let you correct this were simply not exposed by the installed driver.

So I went to the source. Beelink did not offer a driver download for this card, so I grabbed the official package for the exact same Realtek chip from Lenovo’s support site instead, uninstalled the current one, and installed the OEM version. The version number changed, so the update definitely took. The behavior did not change at all. Still WiFi 4, still 20 MHz, still 72 Mbps. A newer official driver, same locked-down result.

That was the moment it clicked that this was not a stale-driver problem. The stock and OEM drivers for this card simply did not give me the controls I needed, and they were happy to leave the card stuck in its cautious fallback mode forever.

The Fix: A Community Driver Called RTK Killer

Digging deeper into forums, I found other people with the exact same RTL8822CE symptom: WiFi 5 hardware behaving like WiFi 4, no useful options in Device Manager, official drivers making no difference. In one of those threads someone had packaged a modified Realtek driver, informally called RTK Killer, built specifically to unlock the behavior the stock drivers hide.

I did this carefully, because swapping in a modified network driver is not something to rush:

1. In Device Manager, I uninstalled the adapter and checked the box to remove the driver software, so Windows would not just reload the old package.
2. Restarted, so nothing from the previous driver stayed resident.
3. Installed the RTK Killer driver.

After the reboot, the change was immediate. The adapter reported WiFi 5, and the aggregated link speed jumped from 72 Mbps to 520 Mbps. A real speed test right after confirmed it: 190+ Mbps, right in line with my MacBook and Mac mini on the same network.

The hardware had been capable the whole time. It just needed a driver willing to let it negotiate the connection it was built for.

Why This Happens

An 802.11ac card falling back to 802.11n on a 20 MHz channel is not a hardware fault. It is a negotiation outcome. The card, the driver, and the router agree on a set of parameters when they associate, and sometimes that handshake settles on the most conservative option and never renegotiates upward. Normally you would nudge it back with the advanced adapter settings: force the wireless mode, force the channel width. When the driver refuses to expose those settings, you lose the one lever that would fix it, and you are stuck with whatever the handshake decided.

That is the real lesson here. “WiFi 5 hardware” only means WiFi 5 speeds if the driver actually lets the chip use its full capability. A locked-down driver can quietly downgrade a perfectly good card, and no amount of reinstalling the same locked-down driver will change that.

Lessons Learned

1. Measure before you theorize. Comparing the mini PC against two known-good machines on the same network instantly ruled out the ISP and the router and pointed straight at the one device.
2. The link speed is the diagnosis. A 72 Mbps aggregated rate on a 5 GHz 802.11ac card is a red flag on its own. It tells you the card fell back to a narrow channel long before you check anything else.
3. A version bump is not a fix. The OEM driver installed cleanly and changed its version number, but it carried the same limitation. Confirm the behavior changed, not just the build.
4. Missing options are a symptom. When Device Manager has no wireless-mode or channel-width controls for a card that clearly supports them, the driver, not the hardware, is the thing holding you back.
5. Community drivers can be the answer, with care. A modified driver like RTK Killer fixed in one reboot what the official packages could not. Clean out the old driver first, and only trust packages that other people with the same chip have actually used.

The card was never the problem. The software wrapped around it was. Once I gave it a driver that trusted the hardware, a machine that could barely hit 10 Mbps was suddenly keeping pace with everything else in the house.