While Qubes is based on Fedora, the fact that it runs the Xen hypervisor and creates a couple of virtual machines means that it inevitably uses more resources. Indeed, Qubes requires a 64-bit processor, and the developers recommend 4GB of RAM, 20GB of disk space and a fast SSD. If your processor features Intel VT-d or AMD IOMMU technology, driver domains such as those for the network and USB devices are isolated, which makes for an even greater level of security.