On a scan my mainboard is an sis741. I am trying to find an instruction manual for this. Is the motherboard the same as the mainboard. The scan also says i have 4 memory slots but when i opened the case i can only locate 2. I am a complete novice as you can probably tell & would appreciate any help. I have looked at the motherboard but cannot identify it. My pc was built by a friend i no longer see.