Hello, I'm new to this forum but I was wondering if you were able upgrade your memory. I have recently acquired this laptop that's equipped with the i5-8250U with integrated graphics. It currently has a single stick of 8GB memory and I tried to upgrade it to 2 sticks of 16GB for a total of 32GB but I end up with a blackscreen and can't even get into BIOS. However when I remove one of the 16GB sticks it will boot into windows but I may get a bluescreen or it may just freeze up. So far I tried 3 different brands of memory and they all pretty much end up with the same results. I also found and installed another 8GB stick to match my original 8GB stick as close as to the specs of it but the same thing happens when both sticks are installed. With just one 8GB stick the laptop runs perfectly fine. Was wondering if this laptop can only run in dual channel mode if both sticks were only 4GB, or do I have to purchase both 16GB sticks directly from Dell. Any info or advice would be greatly appreciated.

did you ever figure this out? because im wondering the same thing.

That system can accept two 16 GB RAM sticks for a total maximum of 32 GB. That's according to Dell's specifications, Crucial web site and Kingston web site. 

Crucial shows compatible RAM on their site. You don't have to use Crucial, but if you don't then find a vendor who will accept return with refund if it doesn't work for you. Crucial guarantees theirs to work or will refund.

Follow instructions in Dell Service Manual.

Whenever touching components or working inside a computer, wear a grounded wrist strap, also called anti-static wrist strap, ESD wrist strap, or ground bracelet. I know many people do such work without this, but it's a cheap and sensible precaution. Rest the laptop on an anti-static mat or at least a reasonable alternative such as corrugated cardboard.