First of all here are my PC specs incase you wish to compare:
<CPU> i5-4670k @ Stock (for now)
<Cooling> H100i (Noctua nf-f12s)
<Mobo> Asus Z87-A
<GPU> Gigabyte GTX970 G1 Gaming
<Ram> 8GB Corsair Vengeance
<SSD> Samsung 840 EVO 120GB(x2)
<HDD> Seagate Barracuda 1TB
<PSU> EVGA Supernova 750 G2
<Case> Fractal Define R4 w/ Window

Focus of This Guide:
After a long time of tweaking each individual setting and researching the performance impact that they have, I have finally managed to find the perfect balance between smooth gameplay and beautiful visuals. In this guide, I will help you to do the same. This guide is more helpful for GTX970 users, however there are many tips included that will be helpful to any Nvidia card owner.

**NOTE: You should optimise your settings in single player seeing as there is more activity in the world than in online. This will guarantee that you are ready to play and hop between single player and online flawlessly.**

-To get the to the nvidia control panel you must right click on your desktop background and choose 'NVIDIA Control Panel'.
-Once in the control panel, find manage 3D settings under the tab named '3D Settings' in the left column.
-Next, click the program settings tab and choose (gta5.exe). If this does not show up in the list, simply click 'add' and find the game file.

Copy the settings shown below exactly and you will instantly notice a difference in gameplay.
The modified settings are shown in bold.
An explaination of the settings can be found at the bottom of this section.

**NOTE** Multi-Frame Sampled AA (MFAA) is exclusive to GTX900 series users!


Adaptive vsync - This is an nvidia exclusive technology similar to vsync but has many more benefits which are explained here - http://www.geforce.com/hardware/technology/adaptive-vsync *Make sure you do not have vsync enable ingame while adaptive vsync is active or you will have problems.*

MFAA - This is exclusive to GTX900 series card users and it provides a 20-30% preformance increase compared to regular MSAA. Turning up MSAA in the GTAV settings will automatically be overrided by MFAA if enabled in the nvidia control panel. If you want x2 MFAA, make sure MFAA is on in the control panel and ingame x2 MSAA is on. If you want x4 MFAA, make sure MFAA is on in the control panel and ingame x4 MSAA is on, etc.

GTX970 Settings Configuration:
The settings shown in the pictures below are my personal settings which should apply to any GTX970 user. If you try out these settings and still have lag issues or you just don't like them, read the 'Tweaking Settings' sections of the guide. You can also follow the steps in the General Nvidia User section to create your own settings from scratch.

I wish that I could provide a list of recommended settings for each individual graphics card, however I cannot do that without trying the card first. In this section I will help you with the process of finding the perfect settings the same way I did.

-Open GeForce Experience.
-Click the Games tab all the way to the left.
-Choose Grand Theft Auto V and click optimise.

-Launch GTAV and open advanced settings.
-Turn off all of the settings except for the extended shadows slider.
-Try the new settings and see if you like them.

-If there are any problems FPS wise its probably because... **GeForce Experience sometimes has high expectations of your graphics card and equips settings that your card cant handle. If the settings cause lag try lowering each setting one step at a time. Usually when you optimise a game with GeForce Experience the settings equiped are within the ballpark of what your card can handle so you shouldnt have to lower many of the suggested settings before finding a stable FPS. For more information on how to prioritize your settings, visit the 'Tweaking Settings' section of the guide or take a look at the link below.

Here is some information on the most and least demanding settings, that may help you decide which settings to lower first if you are experiencing issues. - http://www.geforce.com/whats-new/guides/grand-theft-auto-v-pc-graphics-and-performance-guide#grand-theft-auto-v-nvidia-multi-frame-sampled-anti-aliasing

The Biggest Tweaks:
The most common tweak for improving performance is using FXAA in MSAA/MFAA's place. This will improve your preformance while still looking decent, however if you are like me, MSAA is a must have.

By far the most demanding setting is grass quality. Having this on very high is asking for lag unless you have an overkill PC, so I recommend lowering this to high. I would not put it on normal though because the preformance gain is minimal and the textures are greatly impacted negatively.

All of the advanced Settings excluding shadow distance should also be saved for Overkill PCs as well seeing how they matter a great deal to FPS.

Keep reflection MSAA off. The fast paced nature of the game prevents you from even noticing such details so it is in your best interest to leave disabled.

More Tweaks:
More information to help decide the order in which you should prioritize your settings can be found here - http://www.geforce.com/whats-new/guides/grand-theft-auto-v-pc-graphics-and-performance-guide#grand-theft-auto-v-nvidia-multi-frame-sampled-anti-aliasing

Open Nvidia ShadowPlay through GeForce Experience and activate the FPS counter (You can use other recording software to do the same thing but Shadowplay is my preference). Open GTAV and watch the the FPS counter as you drive around the map. If you are happy with the FPS then you have sucessfully optimized your GTAV to your liking. If not, refer back to step 3. Remember that if you drive in the wilderness and experience frame dips with any settings, its most likely not due to your system. Even people with SLI Titan X's have problems in the wilderness/mountains.

**LAST NOTE: THE NVIDIA CONTROL PANEL SETTINGS ELIMINATE MICRO-STUTTERING, HOWEVER STUTTER MAY STILL OCASSIONALY OCCUR REGUARDLESS OF YOUR FPS. FOR EXAMPLE, YOUR FPS MAY BE A CONSTANT 60 BUT FREEZES AND STUTTERS OCCUR. IT'S PART OF THE GAME UNTILL FURTHER PATCHES. A TEMPORARY FIX IS TO CLICK 'LEFT ALT + ENTER' TWO TIMES WHILE IN FULLSCREEN MODE**

Here is a video to help you setup shadowplay if you are unsure (Not my video) -

I cannot take credit for originally creating any of these solutions, however I did feel it was necessary to make a simplified guide that included everything in one place. If you have any questions feel free to add me and ask and I will try my best to help you out. Please just leave a comment on my profile saying that you need help before adding me.

Please Like, favorite, and share this if it helped you, I want to know who found this guide to be useful.