Most people relies too much on their hardware and forget that it won't work at its optimal possibilities without a clean and configured software setup. Before configuring and optimizing PRC for FO4 it's important to properly configure its own system for gaming.

• Always keep you drivers, direct-X and runtime libraries up-to-date.

• NVIDIA users have to ditch GForce Experience as it is a useless crappy software fulled with background process that are killing the performances.

• Speaking of which, here is a list of crappy software that, in addition to being bad, have compatibility issues with the mod because they hook into game process or graphics : Steam overlay, EVGA, Afterburner, Avast antivirus, EMET, D3D Overrider, Razer and Logitek utils.
Make sure you do not run anything like that.

• Configure your drivers settings for gaming. As reference here is my driver setup which gives me the best performances possible for all my games.

• Lastly but very important and very underrated; Calibrate your monitor for gaming
It's a cheap way of doing it but it's better than nothing and basically;
If you can read text 1: the game will look too bright and faded. If you cannot barely read text 2: dark tons will clip and the lighting will be off. If text 3 looks tinted: the colors of the game will be off too. Lastly, if text 4 isn't pure white: the game will be too dark with poor contrasts.
I recommend to set the black&white point from the monitor and the gamma from software (driver panel, windows tool or else), as it will impact the way PRC look and trigger some effects. A calibration tool is included within the user gui for those who can't calibrate their gamma otherwise.

Configuring the Enb for Fallout 4
• First toggle the game vertical sync off. -I'm using Fallout 4 Configuration Tool by Bilago for this kind of things-
Use the one from your CG driver instead -adaptive is best- or lock the framerate from the enb menu.

• Next you can configure the Enb to properly use the video memory of your system, this can increase the performances.

To know the right number is pretty simple and all you need to do is to add the size of the ram your graphic card has + the size of the ram your system has then remove how much your Operating System uses.
Remember that ram are multiple of 1024:  256, 512, 1024, 2046, 4092, 8192, 10238, 12286, 16384...

Here's as reference an example with my own system: I've a GTX970 with 4Go + 8Go for my system and a clean&crappy software-free Windows 8.1 using an average of 1,5 Go. That is : 4092 + 8192 - 1536 (but let's say 2048 just to be safe) = 10236 is my VRAM size.

Next open enblocal.ini located in the Fallout 4 main folder with notepad or similar and set "ForceVideoMemorySize=true" and enter your VRAM number after "VideoMemorySizeMb="
Save&quit.Profit.
If you have texture streaming issues, just remove the amount of system memory and only keep the Vram from your CG.

• Lastly, if you're still short on FPS, the best thing to do is to disable the PRC SSAO and to set the shadow quality of the game to medium from the option menu of Fallout 4.
If still not enough then use the FO4 SSAO instead of HBAO+ or even disable it. Lastly change your AA setting to FXAA.
If still not enough then I'm afraid there is nothing more to do about it.

Edges pixelation isn't from PRC or NAC but from the God rays rendering of the game. Google to find the fix.