Super Nintendo Hardware Is Running Faster As It Ages

An anonymous reader quotes a report from 404 Media: Something very strange is happening inside Super Nintendo (SNES) consoles as they age: a component you've probably never heard of is running ever so slightly faster as we get further and further away from the time the consoles first hit the market in the early '90s. The discovery started a mild panic in the speedrunning community in late February since one theoretical consequence of a faster-running console is that it could impact how fast games are running and therefore how long they take to complete. This could potentially wreak havoc on decades of speedrunning leaderboards and make tracking the fastest times in the speedrunning scene much more difficult, but that outcome now seems very unlikely. However, the obscure discovery does highlight the fact that old consoles' performance is not frozen at the time of their release date, and that they are made of sensitive components that can age and degrade, or even 'upgrade', over time. The idea that SNESs are running faster in a way that could impact speedrunning started with a Bluesky post from Alan Cecil, known online as dwangoAC and the administrator of TASBot (short for tool-assisted speedrun robot), a robot that's programmed to play games faster and better than a human ever could.

So what's going on here? The SNES has an audio processing unit (APU) called the SPC700, a coprocessor made by Sony for Nintendo. Documentation given to game developers at the time the SNES was released says that the SPC700 should have a digital signal processing (DSP) rate of 32,000hz, which is set by a ceramic resonator that runs 24.576Mhz on that coprocessor. We're getting pretty technical here as you can see, but basically the composition of this ceramic component and how it resonates when connected to an electronic circuit generates the frequency for the audio processing unit, or how much data it processes in a second. It's well documented that these types of ceramic resonators are sensitive and can run at higher frequencies when subject to heat and other external conditions. For example, the chart [here], taken from an application manual for Murata ceramic resonators, shows changes in the resonators' oscillation under different physical conditions.

As Cecil told me, as early as 2007 people making SNES emulators noticed that, despite documentation by Nintendo that the SPC700 should run at 32,000Hz, some SNESs ran faster. Emulators generally now emulate at the slightly higher frequency of 32,040Hz in order to emulate games more faithfully. Digging through forum posts in the SNES homebrew and emulation communities, Cecil started to put a pattern together: the SPC700 ran faster whenever it was measured further away from the SNES's release. Data Cecil collected since his Bluesky post, which now includes more than 140 responses, also shows that the SPC700 is running faster. There is still a lot of variation, in theory depending on how much an SNES was used, but overall the trend is clear: SNESs are running faster as they age, and the fastest SPC700 ran at 32,182Hz. More research shared by another user in the TASBot Discord has even more detailed technical analysis which appears to support those findings. 'We don't yet know how much of an impact it will have on a long speedrun,' Cecil told 404 Media. 'We only know it has at least some impact on how quickly data can be transferred between the CPU and the APU.'

Cecil said minor differences in SNES hardware may not affect human speedrunners but could impact TASBot's frame-precise runs, where inputs need to be precise down to the frame, or 'deterministic.'

Read more of this story at Slashdot.