AX-Procyon

If I remember correctly, ASUS do use orange for RAM debug light. So it is possible it's a RAM problem. Try raise your SoC voltage to 1.125V to see if that helps. Also ASUS BIOS is really weird, ideally you want to set your intended value in both AMD overclocking menu and main OC tweaker menu.

Some HDD management software allows you to securely erase the drives. Like HD Tune Pro. Or if you can't trust software you can always format the drive first, fill it up with your own garble data, and format again. This should eliminate any possibility of recovering old data.

With more RAM usually you will see less memory clock (=less memory bandwidth) because you put more strain on the memory controller. Depend on the timings of the RAM the results can vary wildly, but with similar timings 3600MHz RAM should provide much better performance than 2666MHz. Though on laptops the BIOS usually wouldn't allow you to increase memory voltage so you usually cannot apply 'XMP' on laptop.

When I try to enable G-Sync for my PG27UQ monitor, I click "Apply", the screen flickers for a few moments, then the NVIDIA Control Panel kind of freezes with a thinking wheel. After all that, the G-Sync tick box just reverts to unchecked state again. I am running the newest drivers (436.48 DCH), and resolution set to 3840*2160 at 98Hz with 10 bit color. Windows HDR settings is set to on (and the symptom persists with HDR off). The display is connected to 2080Ti FE via Displayport cable. Is there any fix or workaround to resolve this? In addition, is G-Sync really necessary in non-FPS games and daily use?

My current rig is built inside a 280x case. For your reference, I am running RTX 2080Ti Founders Edition and a Kraken X52. The radiator is sandwiched by X52 stock fans and Corsair LL120 fans. The results can be seen in my photo: there is zero space between the card and the fans, but they are not pushed against each other. The space is just about right - though you have to remove the radiator first before swapping your graphics card and access some components on the motherboard which kind of sucks. If you plan to run your radiator with just 2 fans instead of being sandwiched then I guess most graphics card should be fine. Also if your USB 3 connector is at the bottom of the board you probably cannot put your radiator at the bottom of this case because they interfere with each other.