hardware drivers

The x86 architecture allows users to run operating systems from the 1990s on modern hardware. Yeo Kheng Meng successfully booted Windows 98 SE on a 2020 ThinkPad P12s Gen 1 alongside Windows 11 and Linux from a single NVMe drive. He previously ran MS-DOS 6.22 on a 2020 ThinkPad X13. The main challenges included UEFI complexities and the need for compatible hardware drivers. Both ThinkPad models support UEFI-CSM mode. To address the lack of xHCI support in Windows 98, Yeo used a USB 2.0 expansion card through a Thunderbolt dock. The installation involved disabling Secure Boot, enabling UEFI-CSM, activating Thunderbolt BIOS assist mode, and turning off Kernel DMA protection. Yeo used the CREGFIX DOS driver for stability and applied patches from Rudolph Loew to overcome Windows 98's RAM limitation of 512 MB. Users must rely on basic VESA support and the SoftGPU driver for graphics acceleration due to the absence of updated drivers from Intel and NVIDIA. Disk access is routed through the BIOS, leading to suboptimal performance. Yeo configured the BIOS to support the S3 power state to address ACPI support issues. UEFI-CSM is often overlooked in newer systems, complicating the installation of Windows 7 and contributing to divides in the x86 ecosystem.