Most definitely. A 32-bit operating system can't naturally map more than four gigs of memory, and since Windows uses its four gig address space to map component memory before system memory, Windows 32-bit can't naturally map more than 3.2 Gigs. To enable PAE is to enable an ugly hack that will greatly reduce your system's performance and stability. Note that I have no direct experience, as I've never enabled the switch myself. However, in reading other's experiences, and in understanding what goes on behind the scenes, I honestly believe it's a bad idea.
Without going into too much technical detail, basically /PAE causes Windows to juggle address spaces and mappings so that it thinks it can "see" more memory than it can. Even then, a 32-bit program needs to explicitly understand that this juggle is going on in order to take advantage of the extra utilized RAM (meaning it needs to be PAE aware,) and very few common apps are (to my knowledge.) Furthermore, many apps that aren't perfectly behaved (and most aren't) will likely crash with PAE enabled.
Performance will definitely be slower than a 64-bit native system, as the OS has to continuously perform expensive operations to make PAE work, and even then, it's known to be horribly buggy and unstable.
![[H]ard|Forum](/styles/hardforum/xenforo/logo_dark.png){kind=logo}