have you tried updating clover?
Yes, running newest version. Ive tried all sorts for things from here and there. It seems directly related to the High Sierra drivers and specific hardware. Mostly "boost" and OC versions. Ive been overclocking computers since 1991. Ive done lots, to lots.
Bad drivers. Even rendered video records the corruptions.
5xx, 6xx, 7xx, 10xx cards are displaying problems. Apple and Non-Apple computers.
NOTE: my home build (same system core; Z170, i7 4.4, 32GB PC4 25600) has a GTX 970 with 4GB GDDR5 256-bit memory, 1200 MHz GPU with 1664 CUDA Cores.
Im running 10.13.2 over .3 because SO MANY were having lagging video issues. This .2 high Sierra runs well. I even have Adobe CC Suite installed. PremierPro CC using CUDA acceleration. Everything works! Very happy, powerful Production and Entertainment machine! This is a Fresh build, recently, onto a Samsung PCIe 951 M.2 512GB boot drive. iCloud is 110%
A few days later I went to install the same onto my office machine which is nearly a clone but with a GTX 650 TI and its been nothing but a pain in the ass and a time waster
Although my home build works great my previous install, 10.12.6 looked better. High Sierra display has more saturated color, loss of detail in the shadows. Its disappointing in comparison. Im using a 40" Sony XBR LCD as a display. I use a USB DAC, OnBoard Audio, HDMI Audio and Bluetooth audio. Apple and Logitech BT Keyboards and mice. All working fine. But my Sierra build was also fine and looked better.
Im disappointed in High Sierra overall. Whats the advantage over Sierra 10.12.6?
I DO like the speed of the APFS. its very cool but...
Maybe 10.13.4 and new Nvidia drivers will have it all fixed!
Has Apple hired people from Microsoft or Google lately? Seems like it.