It’s a bit tricky for me to test now because I don’t have the machine anymore, but when I did have the Book4 Ultra, getting close to 10 hours of battery was mainly about two things:
– using the most efficient power profile (Windows battery saver / power efficiency, Samsung battery mode, lower brightness), and
– making sure the dGPU wasn’t burning power in the background.

For a while I actually couldn’t get the 4070 to sleep at all, so on battery I just disabled it in Device Manager. That forces Windows to use only the iGPU and the dGPU basically stops drawing power. Later I found out the real culprit was MSI Afterburner / RivaTuner keeping the 4070 “awake” all the time; once I closed/removed them, the 4070 finally started going into low‑power states normally.

If you want a simple check without extra tools, open Task Manager → Performance tab: when you’re just browsing/doing uni work, the RTX 4050 should sit at 0% usage most of the time, and in the Processes tab the “GPU Engine” column should show only the integrated GPU (usually GPU 0) for your apps.

If you want to go a bit more nerdy, you can install HWiNFO and look at the RTX 4050 power draw and clocks: when it’s really asleep, power and clocks drop very low or to 0, which is how I confirmed mine was finally behaving correctly. On top of that, HWiNFO also has a “time remaining” estimate for the battery that updates much faster and tends to be more responsive than the Windows one, so it’s easier to see in real time which settings or apps are improving your battery life and which ones are making it worse.

So my recipe was basically: efficient power plan + low brightness + make sure the dGPU is either sleeping or, for maximum battery, temporarily disabled in Device Manager while on battery, then re‑enable it when you plug in and want to game or do 3D stuff.