hi guys this is my first post and iam way outa date on my system compared to what i read you all have but my prob is that i have an asus p4xp socket 478 mb wich has a 2.0 celeron everything workks good but i purchasesd a working pentium 2.66 cpu wich i wanted to replace the old 2.0 celeron but when i switch cpu nothing happens there is no post , no beeps etc, i took to my local puter shop and they tried everything from new ram ,bigger psu etc, they tried the 2.66 in another old sys of theres and it indeed works! at the asus site it shows that my board is compatable with the pentium 2.66 ive tried it all but still nothing at all. can anyone please shed some light on this prob of mine, i know it all seems out of date to you guys but its all i can really afford so please help me get me 2.66 working with my asus p4xp board thanx Dragon