Get one with a good integrated processor since you'll be using that for lower frametimes despite whatever your GPU is anyway.
Nvidia Optimus or even some AMD ones have problems with osu! (based on experience with different laptops and also from other forum posts), providing significantly higher frametimes and dropped frames compared to using the integrated graphics processor of your CPU. I reckon it's because of how this game is programmed in the first place.
I currently have an i7-6500U GTX960M and I'm using the CPU's processor with an average frametime of 1.5ms +/-0.2ms compared to the GPU which gives out a terrible 4.0~5.0 ms. That case is the same with my brother's laptop with an AMD GPU.
Takoku wrote:
I recommend the ROG II but evensomething with the relatively weak Nvidia GT940M will at least run nice games on low at 40fps, but the 960M is as much as you'd ever need.
940M is at best a mid-range GPU. It's almost always recommended to play AAA games using this at 1366x768 resolution at low-mid settings, and this will net you a stable 60 fps. Most laptops with a 960M are quite overpriced, tbh. Best to get one during a holiday sale.