ECS P55H-A Black Series offer some good overclocking options under a menu called "M.I.B. II (MB Intelligent BIOS II)". The main options we could see with the initial BIOS release (08/17/2009) were:

• CPU base clock: can be adjusted from 133 MHz to 600 MHz in 1 MHz increments.
• Memory controller base clock: can be adjusted from 133 MHz to 600 MHz in 1 MHz increments.
• PCI Express clock: can be adjusted from 100 MHz to 200 MHz in 1 MHz increments.
• CPU voltage: From +0.01 V to +0.15 V in +0.01 V increments.
• CPU termination voltage (VTT): From +0.01 V to +0.15 V in +0.01 V increments.
• Memory voltage: From +0.01 V to +0.15 V in +0.01 V increments.
• Chipset (PCH) voltage: From +0.01 V to +0.15 V in +0.01 V increments.

Memory timings can also be tweaked.

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Figure 10: Overclocking menu.

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Figure 11: Voltage adjustments.

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Figure 12: Memory timing options.