More On AMD TLB Erratum

As we mentioned last week, AMD has fixed its TLB issues in upcoming silicon. We are still getting questioned on this, so here is an official statement on that direct from Damon Muzny at AMD PR.

The translation look-aside buffer (TLB) erratum number 298 is an L3 protocol issue which can cause a system hang when running certain client workloads. As I mentioned before, it is EXTREMELY unlikely your readers will be able to create a work load that could trigger this erratum. With that said, AMD felt it prudent to fix the erratum in BIOS immediately and in silicon going forward. This TLB erratum has been addressed through a BIOS modification that was provided to our industry partners in November. That BIOS modification was designed to address the erratum and ensure system stability for customers. The chips that are affected are the Phenom 9500 and 9600 processors, and AMD does not anticipate that this erratum will affect any future AMD processors, as it will be fixed in silicon.

The BIOS fix does come with the potential for some performance penalty, depending on software used; however, your readers will be able to download the AMD Overdrive utility with the ability to turn OFF the TLB errata fix and regain full performance. Enabling that switch in AMD Overdrive demonstrates our confidence that this erratum should not be a concern among desktop users. As I have said, though, we have tried to err solidly on the side of caution with our actions and support.

Check with your motherboard builder to download AMD OverDrive or a quick Google search will find a few versions as well. AMD has told us they will not be hosting the utility for a few months, which of course is asinine. “We will build the most awesome CPU overclocking tool ever made, we just won’t actually provide you access to the latest official version.”

As well, you will want to know this about the “Turbo” button in AOD.

Additionally, please note how the three “Turbo” button settings in AMD OverDrive correlate regarding disabling the TLB erratum fix.

Green (top image) = Safe performance level (no TLB caching / default for B2 CPU)

Yellow (middle image) = Elevated performance level (TLB caching enabled… TLB erratum fix turned off)

Red (bottom image) = Highest performance level (TLB enabled + CPU pwr management tweak enabled)

Note: the TLB erratum fix is disabled by moving above the Green / Safe performance level… done so at the user’s discretion, of course.

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