If you have a portable desktop, a giant heatsink air cooler isn't going to be an option. The Cryorig C7 Top Flow CPU Cooler, only 47mm in height, is the perfect cooler to do the task in tight conditions. Even so, the cooler performs much better than stock coolers in any sized case. The heatsink is specifically designed to not interfere with RAM or PCIe cards. Easy to secure, the mounting hardware for the cooler is phenomenal and maintenance-free.