Mark RM :
DRagor :
Wires touching CPU heatsink, any wires, is bad idea. Heatsink gets hot, and this can melt the cable and cause short.
Seriously, if your heatsink gets so hot as to melt the insulator on a wire, your computer will no longer run. Ever.
Thermal damage adds up over time, and it's not a few hours exposition, but rather thousands of hours. So yes, it can do that.