Hi everyone,
I'm looking for help diagnosing an intermittent performance issue with my 250 GB LCD Steam Deck.
After around 15 minutes of gaming, the FPS suddenly drops from approximately 46 FPS to 7–9 FPS. At the same time, the performance overlay shows the CPU dropping to around 400 MHz and the GPU to 200 MHz. The fan keeps spinning loudly, and the temperature reaches approximately 77–79 °C.
The strange part is that the problem lasts for about 20 seconds and then the system recovers on its own. I don't need to close the game or restart the Deck.
What I've observed:
It happens across multiple games.
It happens both while plugged into the charger and on battery.
It does not seem to happen while browsing or watching videos.
The Deck is around 8 months old and was purchased new through Walmart Mexico as a gift.
I haven't opened or physically modified the device, and I don't use third-party performance tools.
What I've already tried:
Restarting the Deck.
Disabling the TDP limit and manual GPU clock.
Checking the FPS and refresh-rate limits.
Entering Battery Storage Mode through the BIOS.
Running Repair SteamOS from the recovery environment.
Resetting the firmware settings.
Unfortunately, the issue still happens.
I'm attaching two screenshots: one taken during the FPS drop and another after the Deck recovers.
Has anyone experienced this exact issue where the CPU/GPU clocks suddenly drop to 400/200 MHz for around 20 seconds and then return to normal?
I'd especially appreciate advice from anyone who found the underlying cause or had this diagnosed by Valve. I'd rather avoid repeating software recovery steps that have already failed.
Thank
Photo 1: Performance drop (CPU at 400 MHz, GPU at 200 MHz, and 7–9 FPS).
Photo 2: Normal performance after the issue resolves itself (CPU and GPU clocks return to normal, and FPS recovers).