I'd use the dell as a baseline, personally. The yellowish tint is based off a different/'more correct' calibration. most consumer monitors are set somewhat too blue out of the box - The colour technology matters too you'll never get a TN and IPS screen identical.
I had a similar switch from a crappy asus to a P2715Q (and a second UHD monitor). Took me a week or so before my eyes got used to the Dell.
That said, when you have mismatched screens, colours are relative - it might be your eyes. Windows 8 onwards has a nice manual caliberation tool. In my case I used my dell as a baseline, then adjusted my second monitor (a cheap korean UHD thing) to get as close to it as possible. Its not identical but better than nothing.