I tried many different ways and the space between the hole of my motherboard are smaller and the bracket that came with my fan is bigger i don't understand why this is my mother board link
XFX nForce 680i LT SLI Motherboard, NVIDIA, Socket 775, ATX, Audio, PCI Express, SLI Ready, Gigabit LAN, SPDIF, USB 2.0 & Firewire, Serial ATA, RAID MB-N680-ILT at TigerDirect.com
and my fan
Thermaltake Max Orb Multi-Socket 775AM2939754 Copper Base CPU Cooler CL-P0369 at TigerDirect.com
as you can see is multisocke !and 775 is included but if you see closely to my motherboard you will see the space around the processor is like a square around the processor
and the bracket that came with my fan is way bigger
check this manual
please What I am doing wrong !!!!!!!!!!!