The exceptions are those that ship with low-end CPUs that don't support the AMD or Intel 64-bit extensions. after Vista's debut) are capable of running 64-bit Windows 7. Most PCs manufactured in the past three years (i.e. Is my PC supported under 64-bit Windows 7?Ī. In speedy Q&A format, here's just what you need to know. A few editions of 64-bit Windows 7 provide a Windows XP Mode that solves some backward-compatibility problems, but it isn't a universal panacea. But if you don't have sufficient RAM (at least 4GB), or you rely on devices that don't have supporting 64-bit drivers, or you need to upgrade an existing 32-bit installation, 32-bit Windows 7 might be the better choice. For most would-be Windows 7 users, a 64-bit version of Windows 7 is the right move.