Did I OC this correct?

Inception9269 · January 1, 2017

Last Thursday I finally built my new pc, it having an i7-6800k cpu, MSI X99A gaming pro carbon motherboard, 32gb of ddr4 3000 ram.

When I first had everything done and put together, it starting up properly, I first set the ram to 3000 using the XMP profile, it worked however after using my pc for awhile and restarting it for an update i went to a black screen and eventually got a message about my overclock, and it going back to default. For awhile whenever I'd try OCing my ram to any speed it would have the black screen issue.

With my cpu I tried overclocking it to 4.0ghz, someone told me to just raise the voltage to 1.2v however it wouldn't work. I'm also unsure of if I'm supposed to raise the ring ratio and what to to OC the ring speed. With my 4790k I typically just had to set the core and ring voltage to the same thing, but that wouldn't work on it.

I was away from my pc for the past few days and left it turned off, but when I came back I gave it another shot. I raised the core voltage to 1.25 volts and started with 3.8ghz, I ran Aida for 15 minutes and it was completely stable and in really good temps. I then went back and bumped it up to 4.0ghz, at 1.27 volts, not touching the ring ratio/voltage at all cause not sure how to go about it. I also tried out raising my ram back to 3000mhz. This time it all worked out perfectly, it running stable in Aida, having ran another 15 minute test. the temps were also really good. With 3.8ghz the hottest core was only at 55c. With 4.0ghz the hottest core was only 65.

Only thing I have to ask I guess, is am I supposed to OC the ring ratio for it to "be considered a true 4.0ghz OC" and if I am to raise the ring ratio, what's the best way to do it, and at what kind of voltage should I set it?

done12many2 · January 1, 2017

Just remember that CPU clock speed trumps all, but yes, you do want to overclock CPU cache (uncore/ring) as high as you can while maintaining stability. In addition to improved CPU performance on CPU intensive workloads, CPU cache also impacts memory bandwidth and latency.

General rule of thumb is that CPU cache should be within 400 MHz of CPU clock speed. Unfortunately, this isn't usually possible with Broadwell-E (BWE) chips. BWE cache generally only reaches 3.7 to 3.8 GHz before it starts to become unstable, while CPU speeds can reach 4.0 to 4.2 (below average), 4.3 to 4.4 (average), and 4.5 to 4.6 (above average).

Your overall overclock is only as good as the weakest link. Often times a CPU's IMC can hold you back from being able to run high RAM clock speed and high CPU clock speed at the same time. Other times, increased RAM speed and CPU cache speed will require additional CPU voltage (VCore) simply because the increased cache and RAM speed increase the workload on the CPU, which is a good thing. Just remember that overclocking one area can and will impact another. The trick is to get them all to play well together.

Inception9269 · January 1, 2017

45 minutes ago, done12many2 said:

Just remember that CPU clock speed trumps all, but yes, you do want to overclock CPU cache (uncore/ring) as high as you can while maintaining stability. In addition to improved CPU performance on CPU intensive workloads, CPU cache also impacts memory bandwidth and latency.

General rule of thumb is that CPU cache should be within 400 MHz of CPU clock speed. Unfortunately, this isn't usually possible with Broadwell-E (BWE) chips. BWE cache generally only reaches 3.7 to 3.8 GHz before it starts to become unstable, while CPU speeds can reach 4.0 to 4.2 (below average), 4.3 to 4.4 (average), and 4.5 to 4.6 (above average).

Your overall overclock is only as good as the weakest link. Often times a CPU's IMC can hold you back from being able to run high RAM clock speed and high CPU clock speed at the same time. Other times, increased RAM speed and CPU cache speed will require additional CPU voltage (VCore) simply because the increased cache and RAM speed increase the workload on the CPU, which is a good thing. Just remember that overclocking one area can and will impact another. The trick is to get them all to play well together.

So what would be a good voltage to set the ring voltage to?

I'll probably just go for setting the ring to 3.6ghz, that being within 400 of 4.0ghz

Inception9269 · January 1, 2017

1 hour ago, done12many2 said:

Tried giving it another shot and just can't overclock the ring ratio without my pc not starting up, me having to clear the cmos each time to get it to do so.

I can get the core frequency to 4.0ghz with my ram at 3000mhz, but I can't raise the ring ratio at all, it being at 3.1ghz

done12many2 · January 1, 2017

3 minutes ago, Inception9269 said:

Tried giving it another shot and just can't overclock the ring ratio without my pc not starting up, me having to clear the cmos each time to get it to do so.

I can get the core frequency to 4.0ghz with my ram at 3000mhz, but I can't raise the ring ratio at all, it being at 3.1ghz

As you increase CPU cache and DRAM speed, you may need to increase cache voltage, DRAM voltage, VCCSA and VCCIO.

This is a very good thread to start poking around in. Great guys with tons of experience with Broadwell-E chips.