OnePlus 15T vs Xiaomi 14 Ultra

OnePlus 15T

The 6.32-inch 165 Hz 1.5K AMOLED panel is the only true 165 Hz compact-flagship display on the market and pairs that refresh rate with a measured 1,800 nits brightness, 460 ppi pixel density, Crystal Shield Glass, and HDR10+/Dolby Vision support. Native 165 Hz support in popular FPS games is a real differentiator. Notebookcheck flags 120.7 Hz PWM dimming that can cause eyestrain for sensitive users.

• The 6.32-inch 165 Hz AMOLED panel achieves a very good 460 ppi pixel density and the advertised maximum brightness of 1,800 nits in standard measurement.
• Display sharpness is plenty competent — sharp, smooth, and easily one of the strongest spec sheets you can get on a compact phone.
• Native 165 Hz support in COD, Delta Force and Peacekeeper Elite makes this the only small-screen flagship pushing a full 165 Hz gaming experience.
• OnePlus claims up to 3,600 nits peak brightness — even on a playground in direct sunlight you can still see everything clearly, no squinting required.
• Specifications confirm a 6.32-inch 1.5K (1216 × 2640) resolution with 165 Hz refresh — a configuration unique to the 15T in the compact class.
• Display backlight flickers at just 120.7 Hz under PWM dimming — low enough that the flickering may cause eyestrain and headaches for sensitive users after extended use.

Xiaomi 14 Ultra

A 6.73-inch 2K LTPO AMOLED with 120Hz, 1920Hz PWM dimming, Dolby Vision and a 3,000-nit peak — a top-tier panel, though measured sustained brightness is good rather than class-leading.

• LTPO AMOLED, 68B colors, 120Hz, 1920Hz PWM, Dolby Vision, HDR10+, 1,000 nits typical / 3,000 nits peak.
• Peak brightness rose from 2,600 to 3,000 nits versus the 13 Ultra; the measured 1,281 nits isn't industry-leading but is excellent nonetheless.
• Notebookcheck's overall verdict scores it 'very good (89%)' — a 6.73-inch 3200×1440 panel among the best flagships.

OnePlus 15T

Snapdragon 8 Elite Gen 5 paired with 12-16GB LPDDR5X Ultra Pro RAM delivers flagship synthetic scores — Notebookcheck recorded Geekbench multi-core 10,976 and 3DMark Wild Life Unlimited 29,901, on par with the larger Xiaomi 17 and Honor Magic8 Pro Air. The problem is sustained: in the 3DMark Wild Life stress test the GPU drops over 50% and the back of the phone hits 50 °C, which both Notebookcheck and SuperSaf flag as a deal-breaker for long gaming sessions.

• Geekbench 6 multi-core hits 10,976 — flagship-tier and within 1% of the average 8 Elite Gen 5 result, so there is no compromise on the chipset versus larger phones.
• 3DMark Wild Life Unlimited hits 29,901 — 5% above the 8 Elite Gen 5 average and ahead of the Xiaomi 17 with the same chip.
• In the 3DMark stress tests the OnePlus 15T shows a sharp drop in performance of over 50%, which significantly lowers our rating.
• Wildlife Extreme stress test scores swung from 6,990 best loop to 3,743 worst loop in a single run — the chart is 'quite a bit of a bumpy ride' and performance mode did nothing to stabilize it.
• Surface temperatures hit 48.3 °C on the back during stress testing and continued climbing to 50 °C near the camera bump — about 45 °C internal — which seems to be the phone's thermal limit.
• Genshin Impact averaged 60.3 fps over 30 minutes at just 3.2 W power draw, with the phone staying cool to the touch — and Peacekeeper Elite pushed 164.5 fps thanks to native 165 Hz support.
• r/Android's reviewer thread flags the same thermal issue directly: 'Gets kinda hot, over 50 degrees in the corner. This is with its very heavy throttling.'

Xiaomi 14 Ultra

Snapdragon 8 Gen 3 with Adreno 750 and up to 512GB UFS 4.0 puts it among the fastest 2024 flagships, with Xiaomi's IceLoop cooling keeping sustained gaming temperatures in check.

• Snapdragon 8 Gen 3 with Adreno 750 and 512GB UFS 4.0 — Notebookcheck rates it 'very good (89%)' overall.
• It's the reason it makes complete sense to put it against the best flagships — a phone that delivers on all fronts.
• Some camera lag appears only in dimly lit auto-mode scenes — raising EV and adjusting exposure in pro mode cuts it down significantly.

OnePlus 15T

This is the section the OnePlus 15T was built to win. The 7,500 mAh silicon-carbon 'Glacier' cell is the largest ever fitted to a true compact phone — 50% bigger than the iPhone 17's pack in a similar footprint. Notebookcheck measured roughly 1.5 days of real-world endurance at 150 cd/m². Wired charging tops out at 100 W, wireless at 50 W. The only friction points are the missing built-in magnets for MagSafe-style alignment and the still-USB-2.0 port.

• OnePlus relies on a silicon-carbon-based battery with a large capacity of 7,500 mAh for its mini flagship — in our practical battery test at 150 cd/m² brightness, the 15T achieved an excellent battery life of nearly 1.5 days.
• 9to5Google's preview confirms the 7,500 mAh cell carries the same 'Glacier' moniker as the OnePlus 15's battery, so the silicon-carbon structure is here too — 200 mAh more than the larger sibling.
• Even though the phone keeps the same compact size, it now packs a massive 7,500 mAh battery — to put that into perspective, the iPhone 17 Pro Max only has around 5,000 mAh, and this is a 6.32-inch phone.
• Battery life is wild for a phone this size and is actually a hair bigger than the one in the OnePlus 15, which has a noticeably larger footprint.
• 100W SuperVOOC wired charging and 50W wireless mean even the huge cell refills fast — getting through two full days on a single charge feels totally realistic.
• There is no native magnetic Qi alignment — wireless charging works, but accessories require a separate magnetic case for MagSafe-style snap-on functionality.
• r/Android's reaction to the battery is unambiguous — 'Incredible battery life makes the compact smartphone competition pale in comparison' is the actual review-thread headline.

Xiaomi 14 Ultra

A 5,000mAh cell (global) with very fast 90W wired / 80W wireless charging. Endurance is improved over the 13 Ultra but still only middling for the class, and heavy gaming drains it quickly.

• The global Xiaomi 14 Ultra has a 5,000mAh battery — same capacity as the 13 Ultra — and endurance is a step up but doesn't win hearts.
• The biggest improvement is gaming endurance — up 33% over the 13 Ultra's underwhelming 5 hours, no longer miles behind competitors but still not class-leading.
• Charging: 90W wired fills empty-to-full in ~33 minutes (matched in testing), plus 80W wireless to 100% in ~46 minutes and 10W reverse wireless.
• Owners are 'not disappointed' with daily battery life, though some wish screen-on time were a bit better.