The accuracy before calibration in the dedicated sRGB mode is excellent. It’s useful for content creators who work in the sRGB color space, as most colors are accurate. There are still some minor inaccuracies, particularly with the white balance and color temperature, which is on the cold side. Gamma follows the sRGB curve well, but it’s slightly too bright with all content.
Unfortunately, the sRGB mode locks most picture settings, including gaming settings like Overdrive. While it doesn’t lock the brightness, the max brightness is low. However, this is the case with sRGB modes on other monitors, too, as it’s designed for content creators working in a dark room. If you want to access most settings and increase the brightness, you would need to use another mode that’s still accurate but has oversaturated colors, as you can see here.
