Do not cut a PM991 only the PM991a can be cut to exactly 30mm. The 991 is about 40mm when cut : r/SteamDeck
Product Details
SAMSUNG PM991A PCIe NVMe M.2 2230 MZ-9LQ512A 512GB SSD For Steam Deck HP Laptop | eBay
PROVANTAGE: Samsung MZ-V9E1T0B/AM Samsung 990 EVO NVMe M.2 1TB SSD
Samsung 990 EVO 1 TB Solid State Drive - M.2 2280 | Beach Audio
Samsung 990 Pro SSD review: The pinnacle of Gen 4 SSD performance
I tried the Samsung PM991 hack and it didn't work. Validate drive before I cut. Cut past the chips like other posters. Now drive only shows up as 1.1gb and won't format.
Samsung PM991 Internal SSD, 256GB PCIe Gen3 x4 NVMe Solid State Drive, M.2 2230 M Key, Speeds up to 2000 MB/s read and 1000 MB/s write, OEM Package - Newegg.com