i am using the same system hp compaq dx6120 mt, after downgrading the processor from pentium 4 3.2ghz to 2.66ghz,(troubleshoot it with micro stepping update and had no more problem with booting) i had a little problem, whenever i first boot, my sound card is not detected, what i do is disable it first in the device manager then enabling it, it will work fine, but again the next time i boot, it is not working and not detected again. my soundcard is an allegro ess, i had the driver downloaded only,but i can see it is signed and it's installed just fine. I want to use a pci sound card add-on so my onboard system will not fail immediately to preserve it of course. thx for the faqs. here is my email if anyone will be able to send answer to this tnx to all.