A Direct Comparison of Heat Control and Real-World Gaming Speed

The OnePlus 15 and Redmi K70 Ultra both target users who push their phones hard, but they do so with different priorities. The OnePlus 15 aims for top-tier stability and sustained speed, while the Redmi K70 Ultra focuses on strong value and aggressive hardware for its price. When gaming becomes the benchmark, the differences in thermal control and long-session performance become easy to spot.

The OnePlus 15 uses a flagship-class chipset built for high-intensity gaming, allowing it to maintain higher frame rates with fewer drops over longer sessions. Its thermal management is tuned to keep performance consistent even during extended play, making it well-suited for graphically demanding titles. The Redmi K70 Ultra also offers strong gaming output with its high-end chip, but its sustained stability varies more noticeably under heavy load.

Thermals are a key differentiator. The OnePlus 15 stays cooler for longer and avoids rapid heat build-up during continuous gameplay. This results in fewer instances of throttling, meaning the phone does not slow down as quickly when things get intense. The Redmi K70 Ultra, although fitted with an enhanced cooling system, tends to heat up faster in high-load games, leading to occasional performance drops in longer sessions.

Frame stability highlights this difference clearly. The OnePlus 15 manages to keep its frame rates steady even in extended gaming scenarios, especially in titles that push the GPU heavily. The Redmi K70 Ultra performs well at the start but shows dips as temperatures rise. This makes the OnePlus 15 more reliable for competitive gaming where consistency matters more than peak numbers.

Battery endurance during gaming also leans in favour of the OnePlus 15. Its larger battery and efficiency tuning let it run demanding games for longer without overheating or draining too quickly. The Redmi K70 Ultra offers good runtime for its class, but its thermals can accelerate battery consumption when gaming at maximum settings.

Display performance is another area where the OnePlus 15 gains an edge. Its higher refresh support offers smoother visuals, particularly in games that benefit from very fast motion. The Redmi K70 Ultra still delivers a fluid experience with its high refresh rate, but the overall polish and stability of the OnePlus panel feel better suited for long competitive play.

In everyday gaming use, both phones will satisfy casual players, but the gap widens for serious gamers. If you frequently play top-tier titles, run long sessions or need consistent thermal control, the OnePlus 15 stands out as the stronger performer. The Redmi K70 Ultra remains a great value choice, delivering impressive speed at a lower tier, but cannot fully match the sustained performance of the OnePlus.

Ultimately, the decision depends on what type of gamer you are. For maximum stability, longer gaming endurance and better heat management, the OnePlus 15 is the superior pick. For excellent performance per cost and short-burst gaming sessions, the Redmi K70 Ultra remains a compelling alternative.