RTV endorses dgVoodoo

[Spiller]

Introduction

GTA:VC runs on DirectX 8.1, which dates back to 2001. Being more than 2 decades old, the API is not widely compatible with modern features of new hardware. 

dgVoodoo is a graphics wrapper that converts old graphics APIs to Direct3D 11 (D3D12 supported from v2.7).
It comes with a collection of .dll files that you can place to fully utilize your hardware.

Why use it?

It is common in laptops to render using only the integrated card even though it is the discrete card working under the hood. Dx8 does not support hybrid setups — as a result, your game will run only on the integrated card unless you have Advanced Optimus or a MUX switch.

If you're on a laptop with a hybrid GPU setup, and are unable to get your game to run on your discrete GPU, you can use dgVoodoo to make it possible. You will be able to use features such as GeForce Experience if your GPU supports it.

Another reason would be to get rid of the stuttering that occurs every few seconds or choppy gameplay even though FPS counter always says 60.

It does NOT

• Necessarily boost your FPS.
• Work well with older AMD GPUs¹.

How to use it?

1. Download it from its official website or github repository.

2. Extract dgVoodooCpl.exe, dgVoodoo.conf and MS/x86/D3D8.dll from the archive to your game directory.

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2b. If you're on hybrid hardware with discrete Nvidia GPU, you'll first need to set the dgVoodooCpl.exe to run with your discrete card from Nvidia Control Panel.

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3. Run the dgVoodooCpl.exe and set Adapter to use as your discrete GPU on the General tab.

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4. On the DirectX tab, untick dgVoodoo Watermark and tick Force vSync, you can leave everything else as is.

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5. Hit Apply and OK. That's it!

DLLs and VCMP

If you were wondering if it is considered "cheating" to use dgVoodoo since it's a .dll file — well not really, not all .dll files are hacks. We whitelist and encourage the use of dgVoodoo in our server. However, you will get kicked (or even banned) for using such stuff outside RTV.

Since dgVoodoo is regularly updated, I'll keep a list of currently whitelisted versions here:

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• v2.78
• v2.75.1
• v2.54

If it still doesn't fix stuttering
Well I guess the issue lies somewhere else then. You can follow below steps to see if that fixes it instead:

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Disable fullscreen optimizations
This feature is, arguably, a joke.

Change config in Nvidia Control Panel

Set low latency mode to OFF. Increases the number of pre-rendered frames.

Set vSync to ON.
Set threaded optimization to OFF, this sets affinity to 1 core.

Footnotes
[1] If you're on an AMD GPU, you're likely to have GUI artifacts, if you're on a newer GPU, you can set the output API to D3D12 FL12.0 to fix that. If you're on an older one, you'll need to use dgVoodoo version 2.54 (which, sometimes, is buggy).

[Spiller]

Disclaimer
dgVoodoo is being distributed as a tool to "remove lag", "increase FPS" or "better sync". I would like to clarify, it does NOT necessarily do any of that.

The optimal use case for dgVoodoo is if you have a laptop with multiple GPUs, something like:

Incase of laptops, it is conventional that only the integrated laptop is connected to the screen, but the discrete GPU is used to render all the frames, which are passed to integrated GPU and then to display. 
But DirectX8 (which GTA:VC runs on), does not support multiple GPUs, so it only uses the GPU connected to your screen, GPU 0 in my case and discrete GPU goes unused.

With dgVoodoo, DX8 is converted into an updated version (DX11/12), and this integrated + discrete (hybrid) setup becomes usable again.

But this does comes at a cost, it might introduce input lag, which may result into floaty mouse (mouse feeling heavy). I would like to advise people not to distribute this tool to others as a method of increasing FPS. They should be made aware of the reason as to why this exists. Do not use it unless you're facing similar issues, your game may appear smoother, but at the cost of bulkier gameplay.