Gaming laptops have come a long way in the last few years. The GeForce RTX 40 series mobile lineup even brings the second fastest desktop GPU to notebooks in the form of the RTX 4090 mobile or the AD103. The same chip powers the RTX 4080 desktop with 9,728 cores and 16GB of GDDR6X memory. The bus is 256-bit wide, and the on-die cache comes in at 64MB. The only difference between the RTX 4090 mobile and RTX 4080 desktop concerns the memory and clock speeds.
The RTX 4080 desktop is paired with 16GB of GDDR6X clocked at 22.4Gbps, while the RTX 4090 mobile features 16GB of GDDR6 memory running at 18Gbps. On the shader side, the former attains a maximum boost clock of 2.5GHz, while the latter peaked at 2.4GHz in our testing. With the technical drivel out of the way, let’s look at the numbers.
The GeForce RTX 4090 mobile was paired with the Intel Core i9-13950HX in the Razer Blade 16 and pitted against high-end desktop RTX graphics cards. For ease of comparison, we’ll limit ourselves to 3DMark TimeSpy, TimeSpy Extreme, FireStrike Ultra, and FireStrike Extreme.
In TimeSpy, the GeForce RTX 4090 mobile scores 19,800 points, which gets cut down to 10,400 in TimeSpy Extreme. The desktop RTX 4090 is a whopping 56% and 80% faster than its mobile counterpart in TimeSpy and TimeSpy Extreme. Even the RTX 4080 desktop is over 40% faster than the RTX 4090 laptop GPU in this benchmark.
With notebooks, the performance greatly depends on the thermals and, therefore, the cooling solution. We were rather impressed by the vapor chamber on the Razer Blade 16. While the CPU does hit its TJ Max of 100C, the GPU stays under 80C throughout the benchmark.
This is reflected in the frequency chart. The GeForce RTX 4090 mobile maintains an average of 2GHz with spikes to 2.4GHz now and then, just 100MHz less than the desktop-grade RTX 4080!
Moving to FireStrike, we can see that the gulf between the mobile and desktop parts becomes even wider. The GeForce RTX 4090 desktop is almost 90% faster than its notebook variant in FireStrike Ultra, with a lead of 70-75% in Extreme. The RTX 4080 desktop remains 40-45% faster than the RTX 4090 mobile in the second 3DMark test as well.
The thermals and clock charts were nearly identical to the ones above, so we decided to leave them out. All in all, the GeForce RTX 4090 mobile is a potent mobile GPU, mostly hampered by thermals and clock limitations.
