Обновление. Не знаю, что именно произошло. Но я выключил машину, вынул карту и проверил кабели и т.д. Собрал машину обратно и загрузился, и теперь всё стало отображаться по-другому. Но теперь у меня новые проблемы. Кстати, карта теперь отображается так:
root@pve:~# lspci -v -s 0000:03:00
03:00.0 VGA compatible controller: NVIDIA Corporation Device 2504 (rev a1) (prog-if 00 [VGA controller])
Subsystem: ZOTAC International (MCO) Ltd. Device 4630
Physical Slot: 6
Flags: bus master, fast devsel, latency 0, IRQ 11, NUMA node 0, IOMMU group 50
Memory at c6000000 (32-bit, non-prefetchable) [size=16M]
Memory at b0000000 (64-bit, prefetchable) [size=256M]
Memory at c0000000 (64-bit, prefetchable) [size=32M]
I/O ports at 6000
Expansion ROM at 000c0000 [disabled] [size=128K]
Capabilities: [60] Power Management version 3
Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
Capabilities: [78] Express Legacy Endpoint, MSI 00
Capabilities: [100] Virtual Channel
Capabilities: [250] Latency Tolerance Reporting
Capabilities: [258] L1 PM Substates
Capabilities: [128] Power Budgeting
<?> Capabilities: [420] Advanced Error Reporting
Capabilities: [600] Vendor Specific Information: ID=0001 Rev=1 Len=024
<?> Capabilities: [900] Secondary PCI Express
Capabilities: [bb0] Physical Resizable BAR
Capabilities: [c1c] Physical Layer 16.0 GT/s
<?> Capabilities: [d00] Lane Margining at the Receiver
<?> Capabilities: [e00] Data Link Feature
Kernel driver in use: vfio-pci
Kernel modules: nvidiafb, nouveau
03:00.1 Audio device: NVIDIA Corporation Device 228e (rev a1)
Subsystem: ZOTAC International (MCO) Ltd. Device 4630
Physical Slot: 6
Flags: bus master, fast devsel, latency 0, IRQ 82, NUMA node 0, IOMMU group 50
Memory at c7080000 (32-bit, non-prefetchable) [size=16K]
Capabilities: [60] Power Management version 3
Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
Capabilities: [78] Express Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Capabilities: [160] Data Link Feature
<?>
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel