Unfortunately there are a zillion factors that can affect your Wi-Fi performance, including what band you're using, distance from your access point (router) and obstructions along the way, interference from other devices, interference from other networks, etc. Measuring with an internet speed test from the PC throws yet another variable into the mix. To test your internet speed, it's best to run a speed test directly from your router if it provides one. Separately you can determine your Wi-Fi link speed via the tips provided here. As [NAME] suggested, it may make sense to try connecting explicitly to either the 2.4 GHz or 5 GHz band connection of your router. 2.4 GHz has a slower top speed than 5 GHz but is much more reliable over longer distances. Monitor your status over time to determine what works best. You can also use Wi-Fi analyzer software (e.g. Acrylic Home) to perhaps find a frequency that doesn't interfere with your neighbors' networks. I know you don't want to replace anything, but I've found performance of the PC's internal antenna lacking. (My PC is located one floor and several rooms away from our router.) I'm getting much better performance with a high-powered USB-attached external adapter. Again as [NAME] suggested, if you can manage a wired connection to your router, it will make things a whole lot faster and simpler.
My XPS 8940 averages an internet speed sub-500 kbps. It's been subpar for a while, but now it's borderline unusable. According to the first Google result for internet speed test, I average 0.37 mpbs download speed and 0.66 mbps of upload speed. The first test always has a faster result than the second because of another strange property of my problem, but that's when I believe my internet is more consistent. The first time I tried the test, I got 1 mpbs of download speed and 0.03 mbps of upload speed. Steam thinks I have no internet. Youtube agrees. This is the only computer in the household that experiences issues like this. I'm sending this from my phone. I've tried every common solution. I've uninstalled the Killer Network things. I've changed my DNS server to Google's temporarily. I've updated my drivers. I've disabled all the sleep settings I'm supposed to disable, the hibernation, hybrid sleep, everything. It doesn't matter. I've ran Windows Network Diagnostics countless times. It has one of two results, being: It tells me that my computer is configured correctly but the device or resource (DNS server) is not responding, or it tells me that the connection point between the computer and router is broken. The former is more common. I know that it's lying to me and that my computer is NOT correctly configured because if it was, i wouldn't have this problem.  As for the aforementioned and foreshadowed strange property of my issue, the speed seems to spike when I connect to the network or when I haven't used the internet in some time--I haven't measured it, but it does take time. It's not amazing when it spikes, but it's useable enough. Windows Network Diagnostics told me to reset the modem. The issue with that is that I just did, due to an unrelated issue. My intermet has not improved. My router is an eero, and my modem is a technicolor. I'm desperate. Also, I'd rather not replace anything, even if it seems nigh inevitable.
Wifi Severely Struggling (XPS 8940, Qualcomm Card)