Failing GX270 heatsink fan, what do i order .....

Hi I have a GX270 small form factor, I'm trying to order the part online thru warrantypartsdirect.com, but I'm alittle confused, The two choices are heatsink or processor fan, i'm leaning towards the processor fan as being the part i need , but i'm not a 100% sure. Any insight would be helpful here.