DRIVERIRQLNOTLESSOREQUAL error Microsoft Windows XP Pro. Ive trying to solve this problem for another user. DRIVERIRQLNOTLESSOREQUALSTOP 0x. D1 0x. 00. 00. 00. The system is a Celeron 1. MB of RAM 4. GB HDD. The problem happens infrequently, but always online when opening certain websites. The OS has been completely reinstalled, but the problem continues. Windows Updates have been done, but did not help. Chandler Stereo Digital Echo Manual on this page. Most indications are that it is a driver problem, but how can I narrow down or identify the problem driver with no file or driver name info in the errorAfter uninstalling, rebooting and troubleshooting the laptop, windows tried to find drivers for Unknown Device and failed. Im sure this unknown device has to be. I have built the same machine as you with regard to the processor, motherboard and ram and am still fighting to get 7 Ult 64bit installed and the install. Any help would be appreciated.