Asus ExpertBook Ultra Pairs Intel Panther Lake Power with a Battery Performance Caveat

Intel's Panther Lake processors mark a substantial leap in integrated graphics performance for thin-and-light laptops. At the heart of this advancement is the Arc B390 GPU within the Core Ultra X7 358H processor, which delivers 1.5x to 2x the raw performance of Intel's previous Arc 140 series and AMD's competing Radeon 890M. This generational jump enables thinner devices like the Asus ExpertBook Ultra to handle graphically intensive tasks without requiring bulkier cooling solutions or sacrificing battery life under typical usage.

However, benchmark testing reveals a significant constraint: maximum performance is only accessible when plugged into mains power. When switching to battery, the ExpertBook Ultra's graphics performance drops by 10-15% across synthetic and real-world tests. This limitation is explicitly enforced by Asus's software layer. The MyAsus control center displays a red warning stating "this performance mode is not supported when using the battery as the power source" when users attempt to engage the highest performance profile.

3DMark Fire Strike Performance (Plugged In)

3DMark Fire Strike (Battery Power)

The performance delta manifests clearly in gaming scenarios. Running Cyberpunk 2077 on Performance mode while plugged in yields playable frame rates for a thin laptop, but shifting to battery triggers an automatic downgrade to Balanced mode. The difference is visually apparent:

Cyberpunk 2077 Performance Mode (Plugged In)

Cyberpunk 2077 Balanced Mode (Battery Power)

This behavior contrasts with competing thin laptops like Dell's 14 Premium featuring Intel Arrow Lake-H, which maintains closer performance parity between battery and mains operation. The disparity suggests Asus implemented aggressive power throttling to prevent excessive battery drain or thermal buildup when unplugged.

Despite this caveat, the ExpertBook Ultra remains among the fastest 14-inch laptops in its weight class. Its Panther Lake CPU-GPU combination still outperforms most integrated graphics solutions even when running on battery, and the system excels during plugged-in usage. This makes it ideal for mobile professionals who primarily work near power outlets but occasionally need GPU acceleration for creative tasks or engineering applications during transit. Users prioritizing consistent performance across power states may want to compare alternatives, but for those who can leverage its strengths, the ExpertBook Ultra delivers exceptional power density. For comprehensive benchmarks against competing systems, see our full Asus ExpertBook Ultra review.