Relevant lines from ASMedia based x4 SATA card configuring in old Phenon baord
Note 30 atabus configuration entries
Its ppb is reporting x16 (correct) and the card link as x2

pci0 at mainbus0 bus 0: configuration mode 1
pci0: i/o space, memory space enabled, rd/line, rd/mult, wr/inv ok
ppb1 at pci0 dev 2 function 0: AMD RS780 PCI-PCI Bridge (ext gfx port 0) (rev. 0x00)
ppb1: PCI Express capability version 2 <Root Port of PCI-E Root Complex> x16 @ 5.0GT/s
ppb1: link is x2 @ 5.0GT/s
pci2 at ppb1 bus 2
pci2: i/o space, memory space enabled, rd/line, wr/inv ok
ahcisata0 at pci2 dev 0 function 0: ASMedia product 1166 (rev. 0x02)
ahcisata0: 64-bit DMA
ahcisata0: AHCI revision 1.31, 32 ports, 32 slots, CAP 0xee349f3f<SXS,PMD,SAM,ISS=0x3=Gen3,SAL,SALP,SSS,SSNTF,SNCQ,S64A>
ahcisata0: interrupting at ioapic0 pin 18
atabus0 at ahcisata0 channel 0
atabus1 at ahcisata0 channel 1
atabus2 at ahcisata0 channel 2
atabus3 at ahcisata0 channel 3
atabus4 at ahcisata0 channel 4
atabus5 at ahcisata0 channel 5
atabus6 at ahcisata0 channel 8
atabus7 at ahcisata0 channel 9
atabus8 at ahcisata0 channel 10
atabus9 at ahcisata0 channel 11
atabus10 at ahcisata0 channel 12
atabus11 at ahcisata0 channel 13
atabus12 at ahcisata0 channel 14
atabus13 at ahcisata0 channel 15
atabus14 at ahcisata0 channel 16
atabus15 at ahcisata0 channel 17
atabus16 at ahcisata0 channel 18
atabus17 at ahcisata0 channel 19
atabus18 at ahcisata0 channel 20
atabus19 at ahcisata0 channel 21
atabus20 at ahcisata0 channel 22
atabus21 at ahcisata0 channel 23
atabus22 at ahcisata0 channel 24
atabus23 at ahcisata0 channel 25
atabus24 at ahcisata0 channel 26
atabus25 at ahcisata0 channel 27
atabus26 at ahcisata0 channel 28
atabus27 at ahcisata0 channel 29
atabus28 at ahcisata0 channel 30
atabus29 at ahcisata0 channel 31

Relevant lines from ASMedia based x4 SATA card not configuring in LGA1700 board
The ppb to which it is atatched is reporting x4 (its an x16 slot) and no card

pci0 at mainbus0 bus 0: configuration mode 1
pci0: i/o space, memory space enabled, rd/line, rd/mult, wr/inv ok
ppb4 at pci0 dev 28 function 4: Intel 600 Series PCH-H PCIe RP 5 (rev. 0x11)
ppb4: PCI Express capability version 2 <Root Port of PCI-E Root Complex> x4 @ 8.0GT/s
pci5 at ppb4 bus 5
pci5: i/o space, memory space enabled, rd/line, wr/inv ok