Aunque luego en un analisis he leido:
So apart from a special black PEG slot (labelled as PCIEX16_2), let's talk about 4-way graphics support utilizing the rest of the orange slots that are labelled as PCIEX16_1, PCIEX16_3, PCIEX8_1 and PCIEX8_2 slots (from top to bottom referring to the photo above). Usually, LGA1155 CPU based boards can only supply 16 lanes for PEG slots and offer very limited bandwidth when there are more than two graphics cards to be supported. However, this monster motherboard spares no expense to equip it with the expensive PLX PEX 8747 high speed switching chip, which takes in the 16 lanes from the processor's PCIe 3.0 controller and fans it out to supply up to 32 PCIe lanes, essentially doubling the bandwidth. This allows the board to support PCIe lane configurations in the following manner - x16/x16, or x16/x8/x8 or x8/x8/x8/x8 - to support dual, triple or quad graphics card simultaneously respectively.
No obstante, si fuera asi, hay placas en 2011 que eran x16 x16 x8 si la memoria no me falla.