Fallout 4 has been in the hands of gamers for a couple of days now, plenty of time for people to compare and contrast the game on different platforms and hunt down early bugs or glitches. That’s exactly what EuroGamer’s Digital Foundry has done and the results are telling.

The first bit of good news is that both the PlayStation 4 and Xbox One render the game at a native 1080p and use temporal anti-aliasing, a fact that the publication says keeps the image sharp and shimmer down even when viewing the sprawling post-apocalyptic world from afar.

Console versions both strive for 30fps gameplay, a modest goal considering the wealth of factors at play such as shadows, characters, day-night cycles and weather systems. Unfortunately, there are some noticeable performance drops to note.

Moving between major city areas, for example, causes both consoles to dip below the 20fps mark in the same spots on the map. This is likely due to assets being decompressed on the fly for the next location and is temporary as frame rates return to normal relatively quickly.

There appears to be a more serious issue with the Xbox One, however, as the game experience can pause for up to a second at a time during play. In matching runs, the Xbox One hit 0fps while the PS4 slowed down to just 28fps. The runs were tested across multiple consoles to eliminate the possibility of a bad box; the issues persisted on all Xbox One machines Digital Foundry tried.

The root cause of these momentary pauses appears to be the Xbox One’s hard drive. Despite an installation size of 28GB, it would seem that the console struggles to pull data from the drive quickly enough. Such stutters are most evident just before a cut scene and when switching to a new weapon using the D-pad. It doesn’t happen all the time but when it does, it can be pretty distracting.

When exploring a complex area such as Diamond City, the team found the PlayStation 4 slightly outperformed the Xbox One (28fps versus 25fps). It’s not a flawless victory for the PS4, however, as the machine struggled in certain scenarios, dropping close to the 20fps mark while Microsoft’s console held firm at 30fps.

In a follow-up report, Digital Foundry concluded that the Xbox One’s storage system is indeed responsible for the bottleneck. Curiously enough, both consoles include a 500GB 5400RPM hard drive yet only the Xbox One suffers from stuttering issues. Short of a title update, the only complete fix at this point is to install a solid state drive in an external enclosure then copy the game data to that drive and use it instead of the internal hard drive (or replace the internal HDD with a SSD). Either way, it’s not a cheap fix but it does eliminate the problem entirely.

Testing with a faster 7200RPM hard drive and a solid state hybrid drive also showed signs of improvement although neither solution completely wiped out the problem the way the SSD did. Conversely, testing a solid state drive with the PS4 provided a very small advantage, one that wasn’t worth writing home about, the team said.

All things considered, the publication believes the Xbox One woes can be corrected via title update considering both platforms have very similar storage solutions and the problems aren’t present on Sony’s machine.

Teardown image courtesy iFixit