Difference between double slottriple slot graphics card?

For instance, we have a Micro ATX motherboard with two PCIe x16 slots, but one is a true PCIe x16 slot while the other is actually a PCIe

Slot, 3-Slot, 3-Slot, 3-Slot, Varies by manufacturer, Varies by manufacturer, 2-Slot, 2-Slot, 2-Slot, 2-Slot Thermal and Power Specs: Maximum GPU Temperature (

20p slot free play Slot, 3-Slot, 3-Slot, 3-Slot, Varies by manufacturer, Varies by manufacturer, 2-Slot, 2-Slot, 2-Slot, 2-Slot Thermal and Power Specs: Maximum GPU Temperature (

20 super slot The case allows for it and having 3 x 120mm fans feeding cool air directly to the GPU will be no problem with + slot cards or less I have 2