It's 318.5mm on length the T1 is only capable of a GPU length of 312.4mm. Buy an EVGA FTW3 3090. Strix won't fit in this case without a waterblock.Asus has updated their website to include more specs.
ROG Strix GeForce RTX 3080 10GB GDDR6X | Graphics Cards
The ROG Strix GeForce RTX 3080 10GB GDDR6X unleash the maximum performance on NVIDIA Ampere Architecture, by featuring Axial-tech fan design, 0dB technology, 2.9-slot Design, Dual BIOS, Auto-Extreme Technology, SAP II, MaxContact, and more.www.asus.com
TUF Gaming GeForce RTX™ 3080
TUF Gaming graphics cards add hefty 3D horsepower to the TUF Gaming ecosystem, with features like Auto-Extreme manufacturing, steel backplates, high-tech fans, and IP5X certifications. And it’s all backed by a rigorous battery of validation tests to ensure compatibility with the latest TUF...www.asus.com
Looks like the strix may be the absolute fattest 3080 that MAY fit. It is really right on the limit of what the T1 supports. And until we try we dont know if the recessed power connectors will clear the top panel. Another thing is that it takes 3 8pins. Can the SF750 or 600 support that?