So schematics won't help you ... your 20 Mhz scope you can use only to repair power supply ... very helpful tool is PC debug cards.. you need get general idea how motherboards work and how they built /CPU,RAM North Bridge, South Bridge/ and you cannot fix motherboards without good soldering skills too./and tools / read "Troubleshooting & Repairing Consumer Electronics Without a Schematic" and you can get some free schematics http://laptop-schematics.com/free-samples/ http://www.badcaps.net/forum/showthread.php?t=7867
more about POST cards http://pctesttool.com/debug card.htm
So schematics won't help you ... your 20 Mhz scope you can use only to repair power supply ... very helpful tool is PC debug cards.. you need get general idea how motherboards work and how they built /CPU,RAM North Bridge, South Bridge/ and you cannot fix motherboards without good soldering skills too./and tools / read "Troubleshooting & Repairing Consumer Electronics Without a Schematic" and you can get some free schematics http://laptop-schematics.com/free-samples/ http://www.badcaps.net/forum/showthread.php?t=7867
more about POST cards http://pctesttool.com/debug card.htm