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As the title suggests setting rising and falling data slopes seems important for overclocking memory if you want to push it a little
If this seems familiar it's probably because I copied and pasted it from my last thread on skew control and changed a few words
I spent an afternoon testing different settings to see just how much difference it makes and it seems it won't even boot with many of them
I can see now that it would be easy to think you were unlucky in the silicon lottery or your IMC isn't any good just because your slopes aren't set correctly
The test I'm using for stability is GSAT. I was using TM5 also but it seems it isn't needed really and just makes the process take longer
There is a GSAT download link and some instructions in my sig if you want to try this for yourself
So my first step was to find a setting I knew to be not quite stable
You might be able to lower VCCSA a little if you aren't getting enough errors. Lowering VCCIO will probably cause freezes
5.2/49 1.32v LLC7
4600-16-17-17-36
1.58vdimm (water cooled)
1.43vccio
1.45vccsa
Next I divided the settings into 4 pairs and set them one pair at a time
Data Rising - Data Falling
CMD Rising - CMD Falling
Ctrl Rising - Ctrl Falling
Clk Rising - Clk Falling
After finding a number that worked with both the rising and falling of the pair I set about finding out which way the pair liked to be offset best. Maybe rising liked to be 1 or 2 values higher or 1 or 2 values lower than falling. Maybe 3.
Once I found the desired offset I could raise or lower the data rising and data falling together as a pair to where it errored least
After doing all 4 sets you can go through them again and see if it helps, but in my case I found the best values first time through
Here are the results
These results laid out in this manor make it pretty clear what my optimum options are for this hardware
Now with skews, slopes and Vref set it was very easy to tighten things up and boost the Aida scores
When I first started setting data slopes I was running 4500c16 daily and 4600c16 tested well some days but not others but now that I have completed the testing and setting it's possible for me to run 4600c16 ram overclock with 2x16GB sticks with similar voltages as my daily
On a side note I think other combinations such as 4600-17-18-18-38 would probably train now and run with lower voltages without much of a performance hit as @PhoenixMDA does
Boots are consistent and rock solid now where-as before I would get the occasional glitch or bad training etc but now it's as stable as when I'm running 4000MHz
My hardware is in my sig for reference
This worked for me on the Apex XII after setting ODT Skews (linked in my sig) and Vref which seems to be just a matter of finding the right value and locking it in (may need adjusting if you make major changes)
If you have some information that may be useful to others with different boards feel free to post it here
Open Office is a free download if anyone would like to try this at home and add your results to this thread for future reference
Be sure to list your parts in your sig or in your post, but it's well worth doing a rig builder in your sig anyway
I look forward to seeing your results
If this seems familiar it's probably because I copied and pasted it from my last thread on skew control and changed a few words
I spent an afternoon testing different settings to see just how much difference it makes and it seems it won't even boot with many of them
I can see now that it would be easy to think you were unlucky in the silicon lottery or your IMC isn't any good just because your slopes aren't set correctly
The test I'm using for stability is GSAT. I was using TM5 also but it seems it isn't needed really and just makes the process take longer
There is a GSAT download link and some instructions in my sig if you want to try this for yourself
So my first step was to find a setting I knew to be not quite stable
You might be able to lower VCCSA a little if you aren't getting enough errors. Lowering VCCIO will probably cause freezes
5.2/49 1.32v LLC7
4600-16-17-17-36
1.58vdimm (water cooled)
1.43vccio
1.45vccsa
Next I divided the settings into 4 pairs and set them one pair at a time
Data Rising - Data Falling
CMD Rising - CMD Falling
Ctrl Rising - Ctrl Falling
Clk Rising - Clk Falling
After finding a number that worked with both the rising and falling of the pair I set about finding out which way the pair liked to be offset best. Maybe rising liked to be 1 or 2 values higher or 1 or 2 values lower than falling. Maybe 3.
Once I found the desired offset I could raise or lower the data rising and data falling together as a pair to where it errored least
After doing all 4 sets you can go through them again and see if it helps, but in my case I found the best values first time through
Here are the results
These results laid out in this manor make it pretty clear what my optimum options are for this hardware
Now with skews, slopes and Vref set it was very easy to tighten things up and boost the Aida scores
When I first started setting data slopes I was running 4500c16 daily and 4600c16 tested well some days but not others but now that I have completed the testing and setting it's possible for me to run 4600c16 ram overclock with 2x16GB sticks with similar voltages as my daily
On a side note I think other combinations such as 4600-17-18-18-38 would probably train now and run with lower voltages without much of a performance hit as @PhoenixMDA does
Boots are consistent and rock solid now where-as before I would get the occasional glitch or bad training etc but now it's as stable as when I'm running 4000MHz
My hardware is in my sig for reference
This worked for me on the Apex XII after setting ODT Skews (linked in my sig) and Vref which seems to be just a matter of finding the right value and locking it in (may need adjusting if you make major changes)
If you have some information that may be useful to others with different boards feel free to post it here
Open Office is a free download if anyone would like to try this at home and add your results to this thread for future reference
Be sure to list your parts in your sig or in your post, but it's well worth doing a rig builder in your sig anyway
I look forward to seeing your results