Highly dependent on your budget, many people have recommended me the DELL U2720Q, albeit a little on the pricey side. If slightly smaller screen then the U2520D. I have been using the DELL U2311H for a good 8-9 years now. Have worked wonders for me. But I just bought the Lenovo P27u-10 and i really love it, colours are great, ports are aplenty and the price for what u get cannot be beat. I paid just over RM1.7k for it coz its on sale with usage of a voucher.

U should go survey the many brands available, I was also considering BenQ, but both the DELL and BenQ was lacking 1 port. I needed 4 ports and they each had 3. Also check out the offerings from LG like the 27UL600.

Since ur doing photoshop, try searching for a monitor which has at least 99% sRGB coverage with a colour accuracy of Delta E<2. If your PC is capable, of course, a 10 bit panel and high adobeRGB coverage (>95%) would be nice, but this comes at a premium and most people do not require it.