Mike's quick and dirty guide to tuning your Clock Skew settings:
1. Setup BIOS
Setup your BIOS/System for your max stable settings in the particular benchmark you want to tweak your memory for. Make sure that the system can handle at least an extra 20mhz FSB 100% stable - you can check this by just using a lower memory divider, while keeping CPU, FSB clocks, voltages, etc. intact. Have the clock skew set to “Normal” on channel A+B.
2. Find Max Stable Setting with “Normal” Clock Skew
Run the benchmark/test at the max stable mem clocks. Now you have your maximum stable memory settings before the clock skew tune.
3. Find best Clock Skew Difference Value
Now check first to see if a different clock skew between channel A and B helps. First only advance channel B by the minimum possible value, check results with your benchmark - Next only delay Channel A with Channel B on Normal, check results, and then reverse delays with advances ...
example:
Test 1: Channel A = Normal / Channel B = Advance 25ps
Test 2: Channel A = Delay 25ps / Channel B = Normal
Test 3: Channel A = Advance 25ps / Channel B = Normal
Test 4: Channel A = Normal / Channel B = Delay 25ps
might only be necessary to run Test 1 + Test 2
After four quick tests you should be able to tell if different values for channel A and B help to stabilize your clocks, or if not you'll know that both channels require an equal value. If different values are beneficial - see if extending the difference shows even more improvement.
You can try advancing and delaying simultaneously - or keeping one channel normal while further extending the difference on the other channel until you find the best difference value.
example
Test 5: Channel A = Delay 25ps / Channel B = Advance 25ps
Test 6: Channel A = Delay 50ps / Channel B = Normal
Test 7: Channel A = Normal / Channel B = Advance 50ps
might only be necessary to run one type of the three variations
Now that you have best difference (or know that an equal value is best), check to see if advancing or delaying both channels will give you any further gains, while keeping the difference from Step 3. between channel A + B ( or keeping equal value) . You should be able to see a trend quickly if you need to delay both channels or advance both channels and be able to zoom in on the best combination for your clock skews.
Examples ( with Clock Skew Difference from step 3 e.g. = Channel A delay 25ps) :
Test 8: Channel A = delay 150ps / Channel B = delay 125ps
Test 9: Channel A = advance 125ps / Channel B = Advance 150ps
You can retest the Clock Skew Difference Value now that you have advanced or delayed by reducing or extending the difference again – but most likely the value will remain identical.
6. Enjoy your improved clocks!
Clock Skews might need to be re-adjusted for different latencies, voltages, dividers and even benchmarks. They should nevertheless be not too far off from what you get from your first clock skew tune.
Clock Skews settings will be different for each different motherboard - even if it is the same model. Don't copy other peoples clock skew settings - they might make things a lot worse for you.
Make sure you remember which order you memory sticks were in the motherboard, as well which slots were used – you might need adjustment if the order is reversed.
Originally Posted by Gautam
Heh, all this talk about clock skew is giving me an idea for that Foxconn article contest.
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. My DOMINATORS were not able to boot into WIN XP at 1000MHz on this board, no matter of volts or timings.
- never had this before.
- the board needs that much.
:
. 
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