[Avery3R]

Most laptops which don't have thunderbolt ports have a pci express card slot that's also vulnerable to DMA attacks.

[pritambaral]

Do you mean ExpressCard? I don't think I've seen a single laptop with an external PCIe slot.

Even so, neither ExpressCard or internal PCIe are used for generic, everyday connectivity (like projectors / external screens). Thunderbolt on Apple laptops is marketed to be used for those.