Imac Mega Upgrade! RAM, CPU To I7 & SSD Upgrade -Still good in 2020 - YouTube
iMac 27" mid 2010 working fine with Patched Sur : r/BigSurPatcher
Amazon.com: DBTLAP Laptop CPU Fan Compatible for Apple iMac 27" A1312 Compatible for Delta BFB0812HD-HM01-9B99 610-0035 069-3742 Late 2009 2010 Mid 2011 Optical Drive Fan Cooling : Electronics
Upgrade iMac Intel Core i3 CPU to Core i7 - iFixit Repair Guide
2010 iMac CPU Upgrade - The whole process - YouTube