Reference Clock Overclocking

[mason marnell@1457018692]

I was just wondering about the reference clock used for over or under clocking. What components would I effect by modifying it and what would happen to them? Thanks!

 

[jimmysmitty]

Are you talking about the BCLK (Base Clock)?

It depends on the CPU. Most newer ones the BCLK has its own clock generator and the only thing it will affect is the CPU frequency. In some CPUs the BCLK generator also controls the SATA clock generator, the PCIe clock generator and others which are all designed to run at 100MHz so if you up it it causes them to fail to work properly. That is why in those CPUs it is preferable to overclock using a unlocked multiplier.

 

[mason marnell@1457018692]

I was talking about the "HT ref. Clock (Mhz)" according to AMD overdrive. I can usually get it pretty high if I turn down the multiplier to even out the normal frequency.

 

[jimmysmitty]

HT for AMD is Hyper Transport. It is the bus link between the CPU and the memory and other components. There is not much of an advantage to overclocking it and again it might have adverse affects to overclocking it beyond its set frequency since it links to the other components.

With a CPU the best overclocking is done with the multiplier these days as you can get much better gains normally. Even on a newer Intel CPU where the BCLK is not tied to the SATA/PCIe etc you might get a few extra MHz out of it and be stable but going much beyond the base clock normally results in massive instabilities. Yet if you leave it stock and up the multiplier you can normally go much higher before running into instabilities.

That is the same with AMD and the HT reference clock.