Inquiries Regarding BCLK Overclocking On Haswell
Inquiries Regarding BCLK Overclocking On Haswell
Does it influence the PCIE bus? (I haven't found clear information online about this.)
What distinguishes a CPU Strap from regular BCLK?
Is a 125mhz CPU strap acceptable?
Why do certain CPUs support higher frequencies when using BCLK plus multi instead of just multi alone?
1. Yes bclk will adjust the PCIE bus speeds, which is often the main reason limiting bclk overclocks; usually only a few MHz can be achieved from bclk.
2. CPU strap is typically used for RAM or Xeon overclocking, but on x99 it's difficult to reach more than 2666mhz without adjusting the CPU strap to 125. Keeping it at 125 ensures other components run at 100mhz, including the PCIE bus. CPU strap is applicable only on x58, x79, and x99 boards. It might be an older model that supports it.
3. Yes it's safe, but you'll need to lower the multiplier if you don't want the CPU to run faster. Currently I'm using 125 with a 37x multiplier, reaching 4625mhz.
4. It varies; generally you'd aim for the highest multi and then extract a bit more performance.
1. Yes, bclk can adjust the PCIe bus speeds, which often restricts how much bclk overclocking can go, usually only allowing a few MHz from the bclk.
2. The CPU strap is typically used for RAM or Xeon overclocking; on x99 it's difficult to reach more than 2666mhz without adjusting the strap to 125. Keeping it at 125 ensures other components run at 100mhz, including the PCIe bus. This setting applies mainly to x58, x79, and x99 boards. It might be supported on older boards, but I'm not sure.
3. Yes, it's safe, but you'll need to lower the multiplier if you don't want the CPU clock to rise too high. Currently I use 125 with a 37x multiplier, reaching 4625mhz.
4. It varies; usually you aim for the highest multi and then extract a bit more from bclk. If you push RAM speeds higher, you'll have to accept a maximum of around 110mhz, which will slightly affect the RAM performance.