In simple terms, the Basic Input/Output System (BIOS) is a small program stored in a computer's motherboard that helps it start up and communicate with its essential components, such as a display device. During the boot process, the BIOS queries the connected display devices for their Extended Display Identification Data (EDID) information, and based on the EDID received, the system then determines the optimal display settings, such as the supported resolutions and refresh rates.
Since the DeckHD display is a completely custom device for the Steam Deck, we need to customise the original BIOS to include the correct display initialisation commands and to let the OS know that we’re booting up with a 1200p display instead of the default 800p. This will ensure compatibility between the computer and the display. Please rest assured, all changes made in our custom BIOS are purely on the EDID side, and we do not tinker with any other components that can affect the stability of the Steam Deck.
We plan to continue providing BIOS firmware support for the foreseeable future. We are also optimistic about having the opportunity to work together with Valve to release official BIOS which natively support the DeckHD screen.
The DeckHD BIOS is also scheduled to be open-sourced in Q4 2023. This is a part of our ongoing commitment to community development and transparency.
Users will need to flash our BIOS firmware each time your Steam Deck upgrades to a newer version of SteamOS. There are currently no workarounds for this as each SteamOS update will revert our BIOS firmware. However, we have made this process as easy as possible for you. Once you have our script downloaded in your Steam Deck’s Desktop Mode, all you need to do is execute and wait a few minutes, then you’re good to go!
In some cases, a white screen will appear when the Steam Deck boots up. A temporary work around would be to force shut down the Steam Deck by long-pressing the power button and powering on again.
Battery drainage comparison when DeckHD screen is running at 1200p vs 800p original screen
We ran both SD's on GTA V online (invite-only session) with a FPS cap at 30 starting from 100% charge. Both SD's were in the same online session, same brightness level, but different resolution (DeckHD at 1200p vs Original SD at 800p). The test duration was around 2 hours and ended when DeckHD's SD powered off first while the original SD had 30% battery remaining. We observed that both SD's had a stable FPS at 30 in GTA V online, but DeckHD's SD consumed ±3W to 5W more power compared to the original SD at any given time.
Battery drainage comparison when both screens are at 800p running the same game from full charge
We ran both SD's on GTA V single player mode with a FPS cap at 30 starting from 100% charge. Both SD's had the same brightness level and resolution (800p). The testing duration lasted just under 3 hours when DeckHD's SD turned off when the original SD had 3% battery left.
We observed that both screens were draining battery equally fast, quite an evenly matched race. Though, at times we observed the SD with DeckHD's screen draws ±0.5W more than the original SD, but it happened frequently the other way too.
Through this empirical evidence, we think it's safe to say that the usage is somewhat identical when both SD's with original and DeckHD screen runs 800p on the same game
For this test case, we loaded a popular indie game - Planet of Lana - on both SD's and carried out the following scenarios:
DeckHD screen at 1200p, original screen at 800p, both with uncapped FPS
When both Steam Decks were uncapped on FPS, we observed a decrease of approximately 20% in the frame rate on the DeckHD screen compared to the original Steam Deck screen. Specifically, while the original Steam Deck was running at around 100 FPS, DeckHD's screen was hovering at a stable ~85 FPS on 1200p. This indicates that the higher resolution on the DeckHD screen, while visually enhanced, may lead to a slight reduction in FPS performance.
DeckHD screen at 800p, original screen at 800p, both with uncapped FPS
To further assess the impact of screen resolution on FPS, we conducted additional tests by setting both Steam Deck screens to 800p. Remarkably, we observed no significant difference in frame rate between the DeckHD screen and the original Steam Deck screen. Both SD's were running at a constant ~100 FPS throughout this scenario.
We observed that although there was a decrease in frame rate when DeckHD screen was set at 1200p, it did not seem that the colour saturation and sharpness of detail of the DeckHD screen was compromised.