I have tried myself inputting the original 512GB drive back in (with windows installed), I have also tried a 1TB SSD with windows cloned from the 512GB drive and I have tried my ROG Z13 Flow 2023's 2TB SSD drive and the ROG Ally boots into BIOS but doesn't recognise any of the 3 SSDs I have tried, yet putting them in my Z13 Flow, they are all recognised.
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