Why is wifi slow on desktop pc but fast on laptop

I've tried reading other similar questions but none of the suggestions help.

I have a new desktop PC. I bought around 5 months ago.

Windows 10, AMD Ryzen 9 3900, 16GB 3200MHz RAM, Intel Wi-Fi 6 (802.11ax)

This is located in my bedroom, approx 15 meters away from the router (in another room). The internet has always been slow and constantly dropping. I assumed it was the wifi card as it was a fairly cheap pre-built pc.

I recently replaced the wifi card with: Ubit AX/AC WiFi 6 Card Dual Band 2974 Mbps AX200

This was giving me speeds of around 16mb/s & was often dropping to around 0.8 - 2mbps. I was constantly spending a good 15 minutes resetting the network adapter/restarting pc before I could use it.

The problem I have is that my laptop/phone etc all have great connections in this room.

I've just run a speed test on google.

Desktop: 0.8mbps download speed.

Laptop: 67mbps

In the exact same spot in the room.

Things I have tried.

1. Replacing the wireless card.
2. Repositioning the pc
3. Restarting the router.
4. Removing the device driver and re-installing them. (I have the latest ones).
5. Preventing Windows from turning off the device to save power (in device manager)

If anyone has any ideas what could be causing the problem, I will be forever greatful.

Is the wireless card that I bought any good? (Link above). It had good reviews.

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