I have a Sony Vaio VPCEB19FX, which has an A222GVPJ motherboard with AMI Aptio Version 1.28.1119, BIOS Version R0300Y8, EC Version K0300Y8, and ME Version 18.104.22.1685 ©2008 Legacy-type BIOS wi Version . I have seen issues reported with booting from USB in this BIOS. I have also seen some specific processor requirements (PAE, NX, and SSE2) and BIOS requirements (NX Bit). Some say non-UEFI BIOS will not work and others say it just limits Win 10 functionality. Others say that AMI BIOS will work and others that you just need to make sure the BIOS will allow a USB boot, by changing a hidden setting to allow the system to boot from USB. This computer meets all other Win 10 requirements, but there is no recent BIOS to flash and I can't see a way to turn on UEFI from BIOS. The manufacturer (Sony) doesn't mention this PC in "supported" PCs able to upgrade to Win 10. The computer is fast and smooth, for an old laptop. To the questions... 1) Is UEFI required? Does Win 10 require anything specific of BIOS? 2) Is the decision by Sony to not list my model due to drivers, UEFI, or just that it has not been tested and, therefore, not officially supported? 3) Is there AMI-specific problem upgrading to Win 10? Am I safe to upgrade from Win 7 to Win 10, with these things in mind? Please help! Thanks in advance!