Intel’s Core Ultra 7 251HX has turned up in PassMark with a small but awkward win over the higher-tier Core Ultra 7 255HX and Core Ultra 7 265HX. The odd part is that Intel’s 18-core chip does it with a lower peak clock, which is the kind of result that makes spec sheets look a little too neat for their own good.
The chip sits between the Core Ultra 5 245HX and Core Ultra 7 255HX, and its early numbers suggest Intel may have built something more balanced than the naming implies. That happens sometimes in mobile parts: thermal behavior, scheduling, and sustained boost can matter as much as raw core count on the box.
PassMark scores for Core Ultra 7 251HX
In PassMark’s single-thread test, the Core Ultra 7 251HX scored 4,666 points, which is about 2% to 3% ahead of the Core Ultra 7 255HX and Core Ultra 7 265HX. In multi-threaded testing, it reached 48,713 points, again landing slightly above the two 20-core models.
- Core Ultra 7 251HX: 18 cores
- Core Ultra 7 255HX: 20 cores
- Core Ultra 7 265HX: 20 cores
- Core Ultra 7 251HX single-thread score: 4,666
- Core Ultra 7 251HX multi-thread score: 48,713
Lower clock, same TDP
What makes the result more interesting is the clock-speed gap. The Core Ultra 7 251HX tops out at 5.1 GHz, while the two higher models reach 5.2 GHz to 5.3 GHz, yet the 251HX still edges them out in this leak. All three chips share a 55 W TDP, so Intel is not getting extra headroom here so much as apparently better efficiency from a smaller core count.
The 251HX had already shown up in Cinebench R23 with strong performance at under 100 W, which points to a pattern rather than a one-off fluke. The real question for laptop buyers is whether that translates into shipping systems that can hold performance without turning into miniature space heaters. If it does, Intel may have an unexpectedly useful midrange HX part on its hands.