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by yencabulator 702 days ago
Except normally the result of a microcode workaround is that the chip no longer performs at its claimed/previously-measured level. Not "as good" by any standard.

For example, Intel CPU + Spectre mitigation is not "as good" as a CPU that didn't have the vulnerability in the first place.
2 comments
burnte 702 days ago
Microcode changes don't have to affect performance negatively. Do you have any evidence this one will? If it's a voltage algorithm failure, then I would expect that they could run it as advertised with corrected microcode. Unstable power is a massive issue for electronics like this and I have no problem believing their explanation. Bad power causes all sorts of weird issues.
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yencabulator 702 days ago
If it was a microcode bug to begin with, fixing the bug wouldn't need to degrade performance. If it was e.g. a bad sensor, that you can "correct" well enough by postprocessing, it doesn't need to degrade performance. But if it's essentially incorrect binning -- the hardware can't function as they thought it would, use microcode to limit e.g. voltage to the range where it works right -- then that will degrade performance.
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burnte 702 days ago
> If it was a microcode bug to begin with, fixing the bug wouldn't need to degrade performance.

This is both a completely untrue statement, and a judgement on a fix that hasn't been released yet.

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sqeaky 702 days ago
At least with spectre applying the mitigation was a choice. You could turn it off and game at full speed, while turning it on for servers and web browsing for safety.

This is busted or working.

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