I have never played Half-Life 2. I own an ancient P2-based Celeron system with an 810 video card. For sound I have one of the original AC97 codecs ever made, the Conexant Riptide chipset. To put it mildly, my computer is old.
Wasn't the big thing about HL2 was, when it was released early, no one could play b/c Valve wasn't allowed to release the activation keys early?