PCI-E lanes in FX processors are on the motherboard in the Northbridge chip , not inside the processor
AMD 970 / 980G motherboard northbridge :
22 + 4 PCI-E 2.0 lanes
Official support for crossfire
No official support for SLI
AMD 990X motherboard nothbridge :
22 + 4 PCI-E lanes
Official support for both crossfire and sli @ x8/x8
AMD 990FX motherboard northbridge :
38 + 4 PCI-E lanes
Official support for crossfire and SLI @ x16/16 OR multi-GPU @ x8/x8/x8/x8
That said , motherboard manufactures may switch lanes between the PCI-e slots so check each motherboard for it's lanes configuration