This is really interesting. The installer really refuses to install IAA2.3 on these systems, but the driver itself recognizes PIIX, PIIX3, PIIX southbridges and what's real surprise, IAA2.3 package contains hidden INF file for these chipsets: (Apologies to those who object to the revival of old threads; and for going off-topic here. It seems like a good place to post this, but I will start another thread in another forum is asked to do so.) So, I want to install Intel Application Accelerator 2x on a laptop with a 440BX chipset (one of those officially unsupported), using the hidden INF discovered by Petr (above). The OS I'm using on this laptop right now is Windows 2000 (again, sorry for the off-topic - although I plan also to try it on a 98SE2ME installation). I unpacked the installer using 7-zip, then used Snoopy's Winpack (mentioned by erpdude8 above) to extract files from the installer's CABs (including the hidden INF, which I then renamed to INTELATA.INF). The driver files for NT+ I could find were INTELATA.SYS, IDECHNDR.SYS, IDEBUSDR.SYS, and IPRTCNST.DLL, and IATAENU.DLL. I tried using the Driver Update wizard to install the extracted driver. The renamed INTELATA.INF was used, but a required file could not be found - IATA2000.DLL. I couldn't find this file in the installer. Does anyone know whether this file is created by the installer during the installation process? If so, could you tell me how to create it without running the installer (and any other required files, for that matter)? I tried a conventional installer-based install, but as Petr said above, it refuses. Does anyone know how to remove the check(s) that prevent the installation?