Assassin's Creed 4 Bogs Down On The PC, Here's How To Fix It

Assassin's Creed 4 Bogs Down On The PC, Here's How To Fix It

Assassin's Creed IV: Black Flag is a gorgeous game, but if you've played it on the PC, chances are you've noticed the erratic frame rate. Whenever the action kicks up, the frame rate drops, often precipitously. This is caused by V-Sync -- if V-Sync is active, the game will only run at either 60 or 30 FPS, and if it can't maintain 60, it'll drop to 30. Unfortunately, turning V-Sync off isn't really an option -- tearing is awful, on both AMD and Nvidia solutions.

Fortunately, there are some things you can do to mitigate the problem, regardless of whether you're an AMD or Nvidia user.


Vexatious V-Sync


Assassin's Creed IV's V-Sync support is oddly implemented. First, the game's engine is capped at 63 FPS, period, no matter what. Turning V-Sync off has absolutely no impact on the maximum frame rate, provided your GPU can reach 63 FPS. Turning V-Sync off will cause tearing and allow the frame rate to move dynamically between 63 and 30 FPS, but it won't allow for anything higher than that.

 
See the jump between 60 FPS and 30 FPS at erratic intervals? That's the behavior we want to eliminate.

Since the game engine can't exceed 63 FPS, you might think that there's no benefit to a higher refresh rate. This is untrue. The way V-Sync is designed to work is this. The game will try to run at the refresh rate of the monitor (usually 60Hz). If it can't, it'll fall back to half speed, or 30 FPS. If it can't maintain 30 FPS, it will fall to 20 FPS.

Unlike most games, which allow the end-user to set the refresh rate directly from an in-game menu, Assassin's Creed IV uses the desktop's refresh rate. If you own a high-end monitor that's capable of a 100Hz refresh rate or more, setting that rate on the desktop will ensure a much better experience. If your monitor can handle a 120Hz refresh rate, for example, that means V-Sync will attempt to hold to 60 FPS. If it can't maintain 60FPS, it will fall back to 40 frames per second. Not only is the gap between 60 and 40 FPS less jarring to the eye, Sustained 40 FPS is far smoother than sustained 30 FPS.



Solution #1 is to increase your monitor's V-Sync setting. If you do, you get a pattern like the above, where you can see performance is split between 44 and 60 FPS, with a few isolated drops below that. But the truth is, there are only a handful of 1080p displays that push above 60Hz. If you own one, great. If you don't, we need a better solution.

Enable Adaptive V-Sync (Nvidia)

Nvidia's Adaptive V-Sync is one way to solve this problem. Adaptive V-Sync works by disabling V-Sync on the fly when the frame rate falls below 60 FPS, and re-enabling it when the frame rate is back at that point. The advantage to Adaptive V-Sync in Assassin's Creed IV over just running with V-Sync off is that Adaptive V-Sync helps reduce the screen tearing that otherwise plagues the game.

To enable Adaptive V-Sync: Right-click on your desktop, choose "Nvidia Control Panel," click on "Manage 3D Settings," and then select "Adaptive" from the Vertical sync options, as shown below.



The impact on the game's frame rate and overall smoothness is significant. The image below shows Assassin Creed IV's performance in 192x1080 with maximum details and FXAA enabled running on a GTX 770. V-Sync is enabled on the left and Adaptive V-Sync is enabled on the right.



The difference between using Adaptive V-Sync and turning V-Sync off is the tearing. Performance-wise, the two modes are identical, but Adaptive V-Sync produces much less tearing then the alternative.

Download Radeon Pro (AMD)

AMD doesn't have an equivalent to Adaptive V-sync supported in its drivers, but there's a third-party utility that can provide the function: Radeon Pro. The latest beta version can be downloaded from the website (this last version adds support for the R9 family of cards). The first thing you have to do to use Radeon Pro is create a profile for the game you want to use. Left click on the green plus, navigate to the Assassin's Creed IV directory (typically C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\games\Assassin's Creed IV Black Flag\ and choose the "AC4BFSP.exe" file as a target.

Then, click on the "Tweaks" tab, find the V-sync setting at the top, and choose "Dynamic" as shown below.


Click to enlarge

With Radeon Pro set for Dynamic quality, the R9 290X's performance profile changes dramatically.



Note that in this case, the reason the R9 290X is pushing a nearly perfect line while the GTX 770 shows variation is due to relative performance -- the R9 290X is the much better card and I don't have a GTX 780 to put up an apples-to-apples comparison. The bigger point is that the problem is solved, for both cards.

Smoother frame rates lead to better experiences

This solution won't magically make the game run faster for everyone -- you still may need to turn detail levels down to hit your preferred frame rate  -- but if the jerky behavior has been annoying you, it should improve the game.

Special thanks to both Nvidia and AMD, where teams on both sides helped me track down this issue
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I turned on triple buffering in the driver settings in catalyst and turned off v-sync in game using an R9 290 and it eliminated %90 of screen tearing. Funny how the game runs better with super sampling enabled over MSAA.

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Their is no native SSAA. You have:

FXAA

SMAA (different type of FXAA)

MSAA

EQAA (custom filter, similar to NVs CSAA).

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I love PC gaming, but times like these I can't help but laugh at all the pc master race losers. I can play AC4 on my PS4 with no problems and beautiful graphics...

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AC4 on the PS4 runs at 30 FPS. Having been playing at that rate to generate this article, 30 FPS sucks.

With a high-end video card and these settings, you can maintain a steady 45 - 60 FPS. I'll take that over the PS4 any day.

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-Game breaks on console-

"Oh well, better luck next generation. :("

-Game breaks on PC-

"Wow, all I had to do was change a setting!"

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Have fun with 720p and 30FPS!

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Game runs in 1080p on the PS4, but nice try. Once again the pc master race comes out with their insecurities. I'll keep my 300+ steam collection, along with my PS4, and have a blast on both.

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"Oh no, he corrected my PC bashing! He must be a PC elitist! Dangit, when will they just let me think I won? OH, I know! How about I pretend to own a gaming PC to people will hold more weight to what I said! Hmm, 300 seems like a believable number."

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Stretched 720 is not 1080, sorry. I'll just enjoy my 4K monitor I got early for Christmas!

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Ok, folks. Let's cool the testosterone.

#1. The PS4 versions of AC4 is true 1080p. Not 720p. Not stretched 900. Sony patched it a few weeks back.

#2. It still runs at 30 FPS. :P And I'll take 60 FPS over 30 FPS any day.

#3. Consoles are great. I sometimes wish I owned an Xbox 360 or PS3, because so many great games have come out for them that never made it to PC. I enjoy great gaming experiences, on any platform, and I wish I'd gotten to play Heavy Rain or The Last of Us.

#4. PCs are great. I love being able to mod games. I love the fact that user communities often pull together and issue patches for titles that developers haven't fixed properly. I love that a game with a vibrant user community can be expanded and stretched far beyond what the developers thought possible, and that this is far more common with PCs than with consoles, though it can happen there as well.

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Console Peasant

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That's a ridiculous statement. People who can afford $400 - $500 consoles and $60 games aren't peasants. Peasants are people living in homes with limited access to electricity, industrial agriculture, and other basic tools of first world infrastructure.

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Well the game is pretty much just a tour of the caribic.... story sucks... so GFX dont matter.

And what is this anyways?

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That's the open source tool FRAFS. It's a frame time viewer.

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Hey guys i play this game on Steam so when i check The Ubisoft Game launcher i didn't see the games folder and i can't select the AC4BFSP. What do i do now?

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