Ubisoft dropped the highly anticipated PC remake of Assassin's Creed Black Flag, dubbed Resynced, and it's a visual showcase—ray tracing, DLSS 4.5 with Multi-Frame Generation, all running on the muscular Anvil Engine. But the early reception isn't all smooth sailing. According to the first 4K benchmarks from DSOGaming, the game stutters badly with ray tracing enabled, and no amount of GPU muscle—not even Nvidia's brand-new RTX 5090—can power through the hiccups.

The rocky launch of a remastered classic

Black Flag Resynced isn't just a texture pack. Ubisoft rebuilt the 2013 pirate adventure in the latest Anvil Engine, the same tech behind recent Assassin's Creed titles. The PC version arrives with full real-time ray tracing for shadows, reflections, and global illumination, plus Nvidia's newest upscaling tech, DLSS 4.5, which introduces Multi-Frame Generation to boost frame rates. On paper, it's a dream. In practice, DSOGaming's testing shows a nightmare: frame-time graphs littered with spikes, stutters that break immersion, and a general sense that the engine is fighting itself whenever the ray-traced lighting kicks in.

These aren't the soft frame rate dips you'd forgive in a bustling Havana harbor. They're sharp, jarring pauses that happen regardless of how overpowered the GPU is. The RTX 5090, still scarce and eye-wateringly expensive, should bulldoze through any title at 4K. Instead, it stumbles like a brigantine in a gale. Ray tracing off? Butter-smooth. Ray tracing on? Prepare for choppy waters.

What this means for your pirate fantasy

If you're one of the lucky few who've already secured an RTX 5090, you might feel a sting. The card was marketed as the ultimate 4K ray-tracing weapon, but Black Flag Resynced refuses to play along. For the majority of players with RTX 40-series, 30-series, or AMD equivalents, the outlook is grimmer: if the problem stems from engine-level threading or RT workload management, weaker GPUs won't escape it, and DLSS 4.5's frame generation can't paper over the cracks—in fact, it might introduce extra latency that makes the stutter feel even more disconnected.

Casual fans who just want to relive Edward Kenway's adventure may not care about ray tracing; they can flip a setting and sail on. But the remake's entire pitch is its visual overhaul. Paying for a remaster that you have to neuter to play smoothly is a bitter pill. And for streamers or content creators who bank on pristine, high-frame-rate footage, this launch is a headache.

Console versions may behave differently—optimizations for fixed hardware often mask these issues—but the PC build's state suggests a port that needed more time in the dry dock.

How we got here: a trail of stuttery ports

Ubisoft's PC history is pockmarked with rocky launches. From Assassin's Creed Unity's infamous face-bugs to Watch Dogs Legion's traversal stutter, the company has often struggled to nail the variable-hardware PC experience on day one. Black Flag Resynced, unfortunately, joins that fleet. But the problem isn't Ubisoft's alone.

Ray tracing, for all its eye candy, remains a performance minefield. Even critically acclaimed implementations—Cyberpunk 2077's path tracing, Jedi: Survivor's RT—inflicted stutter when they first landed. Often the culprit isn't raw GPU power but CPU utilization, shader compilation, or memory management. Anvil Engine, though mature, has only dabbled in ray tracing in recent years; scaling it across an open-world pirate game may have unlocked new bottlenecks.

Nvidia's answer has been DLSS, and the 4.5 iteration is its most ambitious yet. Multi-Frame Generation promises to insert up to three AI-generated frames between every two rendered frames, pushing frame rates to absurd highs. But if the underlying frame pacing is broken, generating more frames only amplifies the inconsistency. DLSS 4.5 can't cure a stuttery engine—it just makes the bad time feel faster.

The RTX 5090 itself is a beast, with a generational leap in shader performance and dedicated RT cores. Its struggles here expose a harsh truth: optimization matters more than teraflops. For early adopters who spent over $1,600 on a GPU, seeing a remaster of a decade-old game stutter is a sobering reminder that top-tier hardware only gets you so far without solid software.

What to do while Ubisoft patches the hull

First, don't panic. If you've already purchased the game and your ship is rocking, try these immediate steps:

  • Disable ray tracing entirely in the graphics menu. This is the nuclear option, but it restores smoothness at the cost of visual fidelity.
  • Cap your frame rate 3–5 fps below your monitor's refresh rate. This can smooth frame delivery and reduce sudden spikes.
  • Experiment with DLSS 4.5 settings. Switch between Quality, Balanced, and Performance modes. Some users report that turning off Multi-Frame Generation and relying on traditional Super Resolution reduces perceived stutter, even if the frame counter is lower.
  • Verify your NVIDIA drivers are the latest Game Ready release for Black Flag Resynced. A driver update specifically optimized for this title could work wonders—keep an eye on GeForce Experience or Nvidia's website.
  • Monitor Ubisoft's official forums and the game's subreddit for user-discovered tweaks. Often, community members find .ini file edits or command-line arguments that alleviate stutter before the developer patches it.

If you haven't bought the game yet, it's wise to wait. Ubisoft hasn't publicly acknowledged the stutter issue as of this writing, but a benchmark as damning as DSOGaming's will force a response. Check back in a week or two. A patch addressing frame-time consistency could land quickly, turning this from a cautionary tale into a redemption arc.

For those on cutting-edge hardware who love to tinker, tools like CapFrameX or RTSS can help you log frame times and pinpoint whether the stutter correlates with specific areas or effects. Such data can guide your settings and inform bug reports.

Outlook: calm seas or more storms?

Black Flag Resynced should have been a triumphant return to one of the series' best-loved entries. Instead, it's become a crash course in the growing pains of ray tracing on PC. Ubisoft's Anvil Engine has proven capable—Mirage ran decently—so the issues here are likely solvable. Nvidia will almost certainly release a driver update that eases the RTX 5090's pain, but the root cause probably lies in how the game dispatches ray-tracing workloads.

The next few weeks will tell whether Ubisoft can right the ship. If you're a PC gamer eyeing this remake, keep your spyglass trained on patch notes. The Caribbean sun still shines, but for now, it's best viewed with ray tracing turned firmly off.