Leak Reveals Alleged Intel Core Ultra X7 358H & Ultra 5 338H “Panther Lake” Performance Comparable to Arrow Lake-H CPUs in Multi-Threading

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The anticipated performance of Intel’s Panther Lake CPUs, specifically the Core Ultra X7 358H and Ultra 5 338H, has recently been the subject of leaks regarding Cinebench R23 MT results.

Predicted Performance of Intel Panther Lake CPUs Compared to Arrow Lake

In a recent revelation, LaptopReview has shared what appears to be the initial unofficial benchmarks for the Core Ultra X7 358H and Core Ultra 5 338H CPUs. These processors are expected to be engineering samples (ES), mirroring the previous testing samples.

The specifications indicate that the Core Ultra X7 358H consists of 4 Performance (P) Cores and 12 Efficiency (E) Cores operational at a boost clock of 4.8 GHz. Meanwhile, the Core Ultra 5 338H features 4 P-Cores and 8 E-Cores with a boost frequency of 4.7 GHz—these figures are derived from recent Geekbench leaks and remain subject to validation.

Alleged Intel Core Ultra X7 358H & Ultra X5 338H 'Panther Lake' Leak Points To Similar Multi-Thread Performance As Arrow Lake-H CPUs

Although the test configurations were not disclosed, both Intel Panther Lake CPUs underwent testing alongside their Arrow Lake-H counterparts. Specifically, the Core Ultra X7 358H was evaluated against the Core Ultra 7 255H, which boasts 6 P-Cores and 10 E-Cores. In parallel, the Core Ultra 5 338H was compared with the Core Ultra 5 225H, which also includes 4 P-Cores, but features 10 E-Cores. Notably, the Arrow Lake-H CPUs operate at higher clock speeds of 5.1 GHz and 4.9 GHz, respectively.

Core Ultra X7 358H: 4 P-Cores + 12 E-Cores @ 4.8 GHz
Core Ultra 7 255H: 6 P-Cores + 10 E-Cores @ 5.1 GHz
Core Ultra 5 338H: 4 P-Cores + 8 E-Cores @ 4.7 GHz
Core Ultra 5 225H: 4 P-Cores + 10 E-Cores @ 4.9 GHz

Turning to the performance metrics, the Intel Core Ultra X7 358H is anticipated to achieve a score of approximately 20, 000 points in the Cinebench R23 Multi-Thread test. Conversely, the Ultra 7 255H from Arrow Lake reportedly scores around 21, 826 points under the same 65W thermal design power (TDP).Additionally, the Intel Core Ultra 5 338H is projected to score 16, 000 points at 60W, while the earlier Core Ultra 5 225H scores 17, 988 points at 65W.

Collectively, these insights suggest that the forthcoming Intel Panther Lake CPUs could potentially match or exceed the performance levels of the Arrow Lake-H series. The Arrow Lake-H ‘Core Ultra 7’ variant benefits from superior and faster P-Cores, while the ‘Core Ultra 5’ variant offers more E-Cores and a higher clock rate. Historically, advancements in silicon production have led to significant performance enhancements in final products compared to initial engineering samples. Intel has also indicated that Panther Lake CPUs may deliver approximately 30% power savings while achieving comparable performance to Arrow Lake-H in multi-threaded applications.

Alongside CPU performance metrics, LaptopReview has also disclosed updated scores for the Panther Lake 12 Xe iGPU in the 3DMark Time Spy benchmark. The optimized results are from a CPU configuration that is presumed to be closer to retail specifications. Previously recorded scores for the Xe3 iGPU were approximately 6300 points, but the latest figures have risen to 6830 points, representing an 8.5% increase. This leap also positions the Xe3 at 55% greater performance compared to the 8 Xe2 iGPU from Lunar Lake.

In summary, Intel’s Panther Lake CPUs are shaping up to be a competitive choice for mobile computing solutions. As with all emerging performance projections, consumers are advised to remain cautious until official benchmarks are released. The first Panther Lake WeU is anticipated to launch within this quarter, with a broader array of processors and a formal debut scheduled for CES 2026 in January.

Preliminary Specifications of Intel Panther Lake-H and U CPUs

CPU Model	P-Cores (Cougar Cove)	E-Cores (Darkmont)	LP-E Cores (Skymont)	CPU Clocks	Xe3 iGPU Cores	iGPU Clock	TDP
Core Ultra X9 388H	4	8	4	TBD	12	TBD	45W
Core Ultra X7 368H	4	8	4	TBD	12	TBD	45W
Core Ultra X7 358H	4	8	4	1.9 / 4.8 GHz?	12	2500 MHz	45W
Core Ultra 5 338H	4	4	4	1.9 / 4.7 GHz?	10	TBD	45W
Core Ultra 9 375H	4	8	4	TBD	4	TBD	45W
Core Ultra 7 355H	4	8	4	TBD	4	TBD	45W
Core Ultra 7 345H	4	8	4	TBD	4	TBD	45W
Core Ultra 5 325H	4	4	4	TBD	4	TBD	45W
Core Ultra 7 360U	4	0	4	TBD	4	TBD	15-28W
Core Ultra 5 350U	4	0	4	TBD	4	TBD	15-28W
Core Ultra 5 340U	4	0	4	TBD	4	TBD	15-28W
Core Ultra 3 320U	2	0	4	TBD	4	TBD	15-28W