content: 32-bit color was not a thing on Windows 3.1 back then IIRC. I had Supermac Spectrum 24 video card that supported the ISA bus that I used on a 486DX-66 machine that had enough video RAM (3 MB) to do 1152x900 at 24-bit color. I ran PhotoShop 3.0 on it but I don't recall it doing real alpha channels. I don't think we got 32-bit color until Windows 95 and graphics card hardware improved as well. Maybe it made its first big appearance when the 3DFX Voodoo hit but it might have been on some earlier cards from S3 or Number Nine. It's been a long time...