Intel Publishes First Microcode Update for Raptor Lake Stability Issue, BIOSes Going Out Now

Following Intel’s run of financial woes and Raptor Lake chip stability issues, the company could use some good news on a Friday. And this week they’re delivering just that, with the first version of the eagerly awaited microcode fix for desktop Raptor Lake processors – as well as the first detailed explanation of the underlying issue.

The new microcode release, version 0x129, is Intel’s first stab at addressing the elevated voltage issue that has seemingly been the cause of Raptor Lake processor degradation over the past year and a half. Intel has been investigating the issue all year, and after a slow start, in recent weeks has begun making more significant progress, identifying what they’re calling an “elevated operating voltage” issue in high-TDP desktop Raptor Lake (13^th & 14^th Generation Core) chips. Back in late July the company was targeting a mid-August release date for a microcode patch to fix (or rather, prevent) the degradation issue, and just ahead of that deadline, Intel has begun shipping the microcode to their motherboard partners.

Even with this new microcode, however, Intel is not done with the stability issue. Intel is still investigating whether it’s possible to improve the stability of already-degraded processors, and the overall tone of Intel’s announcement is very much that of a beta software fix – Intel won’t be submitting this specific microcode revision for distribution via operating system updates, for example. So even if this microcode is successful in stopping ongoing degradation, it seems that Intel hasn’t closed the book on the issue entirely, and that the company is presumably working towards a fix suitable for wider release.

Capping At 1.55v: Elevated Voltages Beget Elevated Voltages

So just what does the 0x129 microcode update do? In short, it caps the voltage of affected Raptor Lake desktop chips at a still-toasty (but in spec) 1.55v. As noted in Intel’s previous announcements, excessive voltages seem to be at the cause of the issue, so capping voltages at what Intel has determined is the proper limit should prevent future chip damage.

The company’s letter to the community also outlines, for the first time, just what is going on under the hood with degraded chips. Those chips that have already succumbed to the issue from repeated voltage spikes have deteriorated in such a way that the minimum voltage needed to operate the chip – Vmin – has increased beyond Intel’s original specifications. As a result, those chips are no longer getting enough voltage to operate.

Seasoned overclockers will no doubt find that this is a familiar story, as this is one of the ways that overclocked processors degrade over time. In those cases – as it appears to be with the Raptor Lake issue – more voltage is needed to keep a chip stable, particularly in workloads where the voltage to the chip is already sagging.

And while all signs point to this degradation being irreversible (and a lot of RMAs in Intel’s future), there is a ray of hope. If Intel’s analysis is correct that degraded Raptor Lake chips can still operate properly with a higher Vmin voltage, then there is the possibility of saving at least some of these chips, and bringing them back to stability.

This “Vmin shift,” as Intel is calling it, is the company’s next investigative target. According to the company’s letter, they are aiming to provide updates by the “end of August.”

In the meantime, Intel’s eager motherboard partners have already begun releasing BIOSes with the new microcode, with ASUS and MSI even jumping the gun and sending out BIOSes before Intel had a chance to properly announce the microcode. Both vendors are releasing these as beta BIOSes, reflecting the general early nature of the microcode fix itself. And while we expect most users will want to get this microcode in place ASAP to mitigate further damage on affected chips, it would be prudent to treat these beta BIOSes as just that.

Along those lines, as noted earlier, Intel is only distributing the 0x129 microcode via BIOS updates at this time. This microcode will not be coming to other systems via operating system updates. At this point we still expect distribution via OS updates to be the end game for this fix, but for now, Intel isn’t providing a timeline or other guidance for when that might happen. So for PC enthusiasts, at least, a BIOS update is the only way to get it for now.

Performance Impact: Generally Nil – But Not Always

Finally, Intel’s message also provides a bit of guidance on the performance impact of the new microcode, based on their internal testing. Previously the company has indicated that they expected no significant performance impact, and based on their expanded testing, by and large this remains the case. However, there are going to be some workloads that suffer from performance regressions as a result.

So far, Intel has found a couple of workloads where they are seeing regressions. This includes PugetBench GPU Effects Score and, on the gaming side of matters, Hitman 3: Dartmoor. Otherwise, virtually everything else Intel has tested, including common benchmarks like Cinebench, and major games, are not showing performance regressions. So the overall outcome of the fix is not quite a spotless recovery, but it’s also not leading to widespread performance losses, either.

As for AnandTech, we’ll be digging into this on our own benchmark suite as time allows. We have one more CPU launch coming up next week, so there’s no shortage of work to be done in the next few days. (Sorry, Gavin!)

Intel’s Full Statement

Source: Recent News