How do I get a 2687W At Max Turbo (3.8GHZ) in a Z420/LJ449AV

[Chip12345]

I upgraded my Z420 from an E5 1650 to the max CPU supported 2687W and have proper/adequate cooling.  At maximum loading using CPU intensive work system is reporting that the CPU is running at 3.4GHZ and at no time do I observe the CPU operating above that - near to what the CPU should support of 3.8GHZ.  I recently flashed to the latest bios and it immediately recognized the CPU when installed.

Any ideas what I should check to get the max potential out of the CPU?  Right now CPU max temperature hit 57C so should have room to run up to 3.8

[MtothaJ · Accepted solution]

---

@Chip12345 wrote:

I upgraded my Z420 from an E5 1650 to the max CPU supported 2687W and have proper/adequate cooling.  At maximum loading using CPU intensive work system is reporting that the CPU is running at 3.4GHZ and at no time do I observe the CPU operating above that - near to what the CPU should support of 3.8GHZ.  I recently flashed to the latest bios and it immediately recognized the CPU when installed.

Any ideas what I should check to get the max potential out of the CPU?  Right now CPU max temperature hit 57C so should have room to run up to 3.8

---

Start by checking In the bios that you have turbo enabled and PCIe Performance mode is disabled.

Also bear in mind that 3.8Ghz is the max speed when only using a single core. If you have 8 cores committed you will get 3.1Ghz. 

This is a multiplier locked CPU so AFAIK no tweeking is possible to get e.g. 3.8Ghz on all cores.  

[Chip12345]

Thanks for the information - I do see all 8 cores/16 threads committed at 3.4GHZ so I'll consider that a win. 

[MtothaJ]

---

@Chip12345 wrote:

Thanks for the information - I do see all 8 cores/16 threads committed at 3.4GHZ so I'll consider that a win. 

---

That seems a normal result and would indicate your system is functioning fine.

. For comparison with the E5-1650 v1 and E5-1650 v2 with all 6 cores / 12 threads committed I had 3.5Ghz and 3.6Ghz respectivelly (vs. max turbo specs of these CPU's at 3.8 and 3.9GHz).