Fixing Windows 11 24H2 BSOD Issues with WD SSDs: A Registry Hack Solution

The world of Windows is teeming with excitement—or rather, a fair bit of consternation—as users of Windows 11's latest feature update, version 24H2, grapple with some pesky bugs. If you've updated your system and noticed those dreaded blue screens of death (BSOD) cropping up, particularly if you are sporting a Western Digital (WD) SSD like the SN770 or SN580, you're not alone. Microsoft has indeed rolled out a feature update that seems to have an array of undocumented bugs, particularly that pesky issue affecting disk performance and stability.

The Problem: BSODs After Update​

Many users have reported that their systems began crashing following the installation of the 24H2 update. The core of the problem appears to stem from a mismanagement of the Host Memory Buffer (HMB) allocations on SSDs that lack dedicated DRAM, specifically the WD Black SN770 and WD blue SN580 models. These SSDs leverage system memory for caching via HMB, meaning that they are particularly sensitive to how that memory is allocated.
But what's this HMB business? It’s a bit like pulling a rabbit out of a hat. This memory buffer technology allows SSDs without DRAM chips to use a portion of system memory for storing data temporarily. The issue arises because, instead of allocating the usual range of 64 MB to 100 MB, some users found their SSDs ballooning this allocation up to 200 MB. This excessive allocation doesn't just rock the boat; it sends the whole ship into a tailspin, resulting in the classic BSOD.

Solution: The Registry Hack​

Despite the complexities behind the scenes, there is a light at the end of this frustrating tunnel in the form of a Registry hack. Here's a step-by-step guide on how to potentially remedy this problem:

1. Open the Registry Editor: Press Win + R, type regedit, and hit Enter.
2. Navigate to the Registry Key: Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\StorPort.
3. Create the HmbAllocationPolicy Subkey: If it doesn't exist already, create a new DWORD value named HmbAllocationPolicy.
4. Modify the Value: Set this DWORD value to either 0 or 2:
   • 0 disables HMB allocation.
   • 2 sets it to 64 MB.
5. Restart Your PC: A reboot is essential to apply the changes you just made.

This tweak alters how the SSD interacts with your system memory, effectively lowering the overhead that’s causing those BSODs.

Why This Matters​

For the uninitiated, understanding DRAM-less SSDs and their workings may seem like diving into the deep end. DRAM caches—on SSDs that have them—act as temporary storage for metadata, improving the read and write speeds of the drive. Drives without this cache use HMB to engage with system memory, and any misallocation can lead to significant performance degradation or system instability, as evidenced by widespread complaints among users.

What’s Next?​

While this workaround may alleviate immediate issues, the underlying cause undeniably requires addressing through an official update from Microsoft or WD. If you've tried the registry hack and found success, consider visiting Microsoft’s Feedback Hub to voice your concerns; those voices collectively help guide future updates.
For those with non-WD SSDs also facing similar issues, feel free to experiment with the same registry changes. It's a stopgap solution while we wait for something more permanent.
As we march bravely into the digital frontier, remember: updates can be double-edged swords, leaving users with both exciting new features and unexpected headaches. Stay curious and keep tinkering!

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With this newfound knowledge, users can take immediate action to address those pesky BSODs. As always, full backups are recommended before making any substantial changes to system settings—you never know when a routine registry edit could turn into an unwelcome surprise!
Source: Neowin Registry hack fixes WD SN770, SN580 Windows 11 24H2 blue screens (BSOD)