Ubuntu 20.04 non-deterministically hanging during boot

I’m experiencing an issue with a new laptop and a fresh ubuntu install. About 30-40% of the time during startup, the laptop will freeze with a black screen. I’ve tried letting it sit for >10min, with no visible effect. I’ve been able to reproduce this

1. After disabling the splash screen in grub
2. Both with and without a monitor plugged
3. I have tried running with nomodeset, and I have not detected a failure in this case. However, I am then unable to connect to an external monitor. It’s also possible that I haven’t detected a failure merely because I haven’t tried running with nomodeset for more than a few minutes (due to monitor issue).

It appears to happen after various parts of ubuntu have been initialized. In particular, with quiet removed from grub’s options it will run through the boot sequence and at the point of transitioning from the scrolling bootlog to the login screen, then it will freeze. I do not seem to be able to change to a terminal either, so it’s rather difficult to debug precisely where things freeze. Once the laptop boots, however, I have not detected any problems!

As mentioned in the title, this is with Ubuntu 20.04. The laptop itself is a thinkpad (t495, type 20NK) with the following output from lspci

00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Root Complex
00:00.2 IOMMU: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 IOMMU
00:01.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge
00:01.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:01.3 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:01.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:01.6 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:01.7 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:08.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge
00:08.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Internal PCIe GPP Bridge 0 to Bus A
00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 61)
00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 51)
00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 0
00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 1
00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 2
00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 3
00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 4
00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 5
00:18.6 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 6
00:18.7 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 7
01:00.0 Network controller: Intel Corporation Wireless-AC 9260 (rev 29)
02:00.0 Non-Volatile memory controller: SK hynix Device 1627
03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0e)
03:00.1 Serial controller: Realtek Semiconductor Co., Ltd. Device 816a (rev 0e)
03:00.2 Serial controller: Realtek Semiconductor Co., Ltd. Device 816b (rev 0e)
03:00.3 IPMI Interface: Realtek Semiconductor Co., Ltd. Device 816c (rev 0e)
03:00.4 USB controller: Realtek Semiconductor Co., Ltd. Device 816d (rev 0e)
04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 10)
05:00.0 SD Host controller: Genesys Logic, Inc GL9750 SD Host Controller (rev 01)
06:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Picasso (rev d1)
06:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Raven/Raven2/Fenghuang HDMI/DP Audio Controller
06:00.2 Encryption controller: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 10h-1fh) Platform Security Processor
06:00.3 USB controller: Advanced Micro Devices, Inc. [AMD] Raven USB 3.1
06:00.4 USB controller: Advanced Micro Devices, Inc. [AMD] Raven USB 3.1
06:00.5 Multimedia controller: Advanced Micro Devices, Inc. [AMD] Raven/Raven2/FireFlight/Renoir Audio Processor
06:00.6 Audio device: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 10h-1fh) HD Audio Controller

I have not deliberately installed any drivers or done anything to modify the standard Ubuntu install (though I did allow for proprietary drivers during install), but please let me know if there is any additional information I should add here.