Furry,
With the iommu grouping on a mobo like x370 Taichi you can probably do what you want or most of it. As an example from my X370 gaming here is the listing with a card installed in both full sized slots, and also nvme drive loaded.
As shown I have the capability to pass through both 8x “GPU” slots, the CPU connected M.2 4x slot, the hd audio, and USB controller. (also some sata ports)
While I haven’t yet tried passing through 2 GPUs, I have tried passing in a GPU and another device in the 8x slot, in addition to the USB and audio simultaneously. USB passthrough gets 4 dedicated ports on the back. No ACS is needed for this. At some point I plan to try the dual gpu and maybe even the nvme slot passthrough (that requires swapping nvme drives around, so a pain)
IOMMU Group 0 00:01.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 1 00:01.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 2 00:01.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 3 00:02.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 4 00:03.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 5 00:03.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 6 00:03.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 7 00:04.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 8 00:07.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 9 00:07.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Internal PCIe GPP Bridge 0 to Bus B [1022:1454]
IOMMU Group 10 00:08.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 11 00:08.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Internal PCIe GPP Bridge 0 to Bus B [1022:1454]
IOMMU Group 12 00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:790b] (rev 59)
IOMMU Group 12 00:14.3 ISA bridge [0601]: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge [1022:790e] (rev 51)
IOMMU Group 13 00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 0 [1022:1460]
IOMMU Group 13 00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 1 [1022:1461]
IOMMU Group 13 00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 2 [1022:1462]
IOMMU Group 13 00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 3 [1022:1463]
IOMMU Group 13 00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 4 [1022:1464]
IOMMU Group 13 00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 5 [1022:1465]
IOMMU Group 13 00:18.6 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric Device 18h Function 6 [1022:1466]
IOMMU Group 13 00:18.7 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 7 [1022:1467]
IOMMU Group 14 01:00.0 Non-Volatile memory controller [0108]: Toshiba America Info Systems Device [1179:0115] (rev 01) [M.2 slot]
IOMMU Group 15 03:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Device [1022:43b9] (rev 02)
IOMMU Group 15 03:00.1 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] Device [1022:43b5] (rev 02)
IOMMU Group 15 03:00.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43b0] (rev 02)
IOMMU Group 15 1d:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 300 Series Chipset PCIe Port [1022:43b4] (rev 02)
IOMMU Group 15 1d:02.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 300 Series Chipset PCIe Port [1022:43b4] (rev 02)
IOMMU Group 15 1d:03.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 300 Series Chipset PCIe Port [1022:43b4] (rev 02)
IOMMU Group 15 1d:04.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 300 Series Chipset PCIe Port [1022:43b4] (rev 02)
IOMMU Group 15 1e:00.0 Ethernet controller [0200]: Aquantia Corp. AQC108 NBase-T/IEEE 802.3bz Ethernet Controller [AQtion] [1d6a:d108] (rev 02)
IOMMU Group 15 20:00.0 SATA controller [0106]: ASMedia Technology Inc. ASM1062 Serial ATA Controller [1b21:0612] (rev 02)
IOMMU Group 15 21:00.0 PCI bridge [0604]: ASMedia Technology Inc. Device [1b21:1184]
IOMMU Group 15 26:01.0 PCI bridge [0604]: ASMedia Technology Inc. Device [1b21:1184]
IOMMU Group 15 26:03.0 PCI bridge [0604]: ASMedia Technology Inc. Device [1b21:1184]
IOMMU Group 15 26:05.0 PCI bridge [0604]: ASMedia Technology Inc. Device [1b21:1184]
IOMMU Group 15 26:07.0 PCI bridge [0604]: ASMedia Technology Inc. Device [1b21:1184]
IOMMU Group 15 27:00.0 Network controller [0280]: Intel Corporation Device [8086:24fb] (rev 10)
IOMMU Group 15 28:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Baffin [Radeon RX 460] [1002:67ef] (rev e5)
IOMMU Group 15 28:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Device [1002:aae0]
IOMMU Group 15 2a:00.0 Ethernet controller [0200]: Intel Corporation I211 Gigabit Network Connection [8086:1539] (rev 03)
IOMMU Group 15 2c:00.0 Non-Volatile memory controller [0108]: Intel Corporation Device [8086:f1a5] (rev 03)
IOMMU Group 16 2d:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:1470] (rev c1)
IOMMU Group 17 2e:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:1471]
IOMMU Group 18 2f:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Vega [Radeon RX Vega] [1002:687f] (rev c1)
IOMMU Group 19 2f:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Device [1002:aaf8]
IOMMU Group 20 30:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM1142 USB 3.1 Host Controller [1b21:1242][PCIe 8x slot passthrough]
IOMMU Group 21 31:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Device [1022:145a]
IOMMU Group 22 31:00.2 Encryption controller [1080]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Platform Security Processor [1022:1456]
IOMMU Group 23 31:00.3 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] USB 3.0 Host controller [1022:145f]
IOMMU Group 24 32:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Device [1022:1455]
IOMMU Group 25 32:00.2 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7901] (rev 51)
IOMMU Group 26 32:00.3 Audio device [0403]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) HD Audio Controller [1022:1457]
Bill