Intel I7 965 @ 5.247Ghz
Gigabyte X58 UD5
3 Stage cascade -100c
Corsair 2133 Dominator DDR3
Voltages
vcore ~1.5v, this is a "leaky" high IDV chip, scaling up with higher voltage is possible at a cost of runaway amp phenomena.
vmem ~2.2v for benching 2v on Vapo, compensate voltage with cooling to be safe.
vqpi ~1.35v depending on the board/bclock, upwards of 1.55v if I am pushing bclock, I run a low bclock so I usually leave it on stock.
vmem is the secret to uclk, 2.2v gets you 4.7Ghz ulck. uclk is also known as uncore.
general ratios
Stock QPI on i7 965 is x48 @ 133 bclock, if you raise the bclock to 160ish you would need to drop qpi ratio to X44 to continue raising the bclock to 180ish, drop qpi again to X36 again and that will get you out the theoretic max bclock of 220. That is not set in stone, some chips/board combos have exceeded these numbers but this rule is pretty close to what you will see on C stepping.
The uclk ratio I prefer to use is (the lowest possible) 1:2 of my ram speed (uclk runs at twice the speed of memory) and at lower speeds there are plenty more ratios to scale higher without running the sick memory speeds that I do, this is a huge gain in performance but for me it requires a lot of vmem and high end memory to run upwards of 2300Mhz (4700Mhz uclk) the memory controller has exceptional is its stability at this speed, I have not reached top speed and it will take even faster ram and more vmem to achieve that.
Runaway amp phenomena, I hook an amp meter to the four yellow wires on eight pin power cable that connects near the CPU. Watching this you will see that yes you can keep scaling up with more voltage but your chip has a limit with all cores loaded that it will runaway on amps till it crashes. I know exactly what range to stay in with cores loaded to know not to hit this runaway threshold. Keeping vcore down and disabling HT lets me run at the chips max speed, HT has an added power load on the CPU, disabling it helps gain critical Mhz.
Max Uncore and QPI, memory speed is correct, SPD 9-9-9-24
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