Set a ratio of 47X at 1.29V and see if you can pass the AVX stress test. Don't use AVX offset until you know what the CPU can manage under an AVX workload. The gap in stability and required voltages under AVX workloads can be considerable, which is why the option was introduced. A mere 10mV difference and 100MHz gap would negate most of its purpose. LLC 7 is quite severe, too. I tend to use a value of 4-5 on these boards, as it compliments the VRM well.
Raja, maybe I haven't explained the situation good enough. In all the cases I'm always using AVX instructions. 🙂 I start with x50|1.30v|AVX-negative-offset 0 and I run the AVX enabled video encoding. Perfectly stable, always. I've tried this 5 times at least, it always gets the job done without problems.
However when I go back to UEFI and set "negative offset" to "1" and voltage to "1.29", the system is no longer stable. You see, both cases are exactly the same workload. Both are with AVX, I'm using the same video file, same encoder settings. The only difference is that in the first case I'm running 5000 at 1.30 (negative offset 0) and in the second case I'm running 4900 at 1.29v (negative offset 1). Furthermore I have already tried setting the "negative offset" to 2 and 3 (4800MHz or 4700MHz respectively) and it's still unstable at 1.29v. It's like at some point the AVX negative offset "stops working" for a split second, the CPU jumps back to 5000MHz instantaneously and given the fact it only has 1.29v it eventually crashes. At least that's what I'm thinking.
Once again here is it as a quick summary:
5000MHz AVX offset 0 @ 1.30v - running AVX-enabled video encoding stable.
5000MHz AVX offset 1 @ 1.29v - same AVX-enabled video encoding results in a crash.
5000MHz AVX offset 2 @ 1.29v - same AVX-enabled video encoding results in a crash.
5000MHz AVX offset 3 @ 1.29v - same AVX-enabled video encoding results in a crash.
Try setting the target load voltage using a different LLC (7 is quite aggressive). You may wish to try using Adaptive voltage, too. And for sake of bing thorough, I'd try higher voltage levels to see how far the gap is. 10mV leeway might not be enough for load modulation. The workload likely modulates a bit, which you can't see.
I'm just trying to set as low Voltage as possible for my non-AVX workloads. Ideally I want to have something like 1.27v for 5000MHz non-AVX loads with AVX negative offset 3 (4700MHz), but so far it seems this setup wouldn't be stable. 4700MHz at 1.27v would be perfectly stable if that's the max frequency (with avx negative offset = 0), but when I'm using avx negative offset = 3 (and the frequency is again 4700mhz) the system won't be stable for some reason.
The applied voltage is not the same for AVX and non-AVX loads. Intel has programmed the VID table differently depending on AVX usage so this is not as cut and dried as one would think. I will have examples and measurement posted up in the next couple of day that demonstrate this.