Issues with 14700k

Hi everyone,

I’m running into some issues with my build, and I’m hoping to get some advice. I recently upgraded to an i7-14700K paired with a old Gigabyte B660M DS3H, and while gaming performance is solid, I’m experiencing some instability in Cinebench R32 and single / multi-core workloads. Here are the details:

Specs:

  • CPU: Intel i7-14700K
  • GPU: EVGA RTX 3080
  • Motherboard: Gigabyte B660M DS3H (latest BIOS with microcode 0x12B)
  • RAM: G.Skill Ripjaws V 32GB (3600MHz, XMP enabled)
  • Cooler: DeepCool AK620
  • PSU: 750W Corsair RMx

The Issues:

  • In Cinebench R23, my CPU clocks and power power draw, CPU temp spiking erratically, causing inconsistent performance and very low scores compared to what this CPU should achieve (e.g., ~645 multi-core score).
  • During gaming (e.g., Assetto Corsa Competizione in VR), I get 100% GPU utilization and smooth, stable performance. Temps stay below 75°C, and CPU clocks hold steady around 5.4GHz.

What I’ve Tried:

  1. Reset BIOS to defaults: I only enabled XMP and Resizable BAR.
  2. Undervolting: Applied a -0.050V offset via Dynamic Vcore (DVID), but Cinebench still shows erratic power and clock behavior.
  3. Disabling E-Cores: Enabled the "Disable All E-Cores for Gaming" profile in the BIOS, which helped stabilize gaming but didn’t fix Cinebench performance.
  4. Turbo Power Limits: Set PL1 = 125W and PL2 = 175W, but the erratic spiking remains.
  5. Monitoring: Using HWInfo64 and MSI Afterburner, I see jumps in power draw, clock speeds, and CPU usage during Cinebench runs.

My Questions:

  1. Could this behavior be caused by the B660M DS3H’s VRM limitations?
  2. Is it normal for Cinebench to behave this way even if gaming performance is fine?
  3. Would upgrading to a Z690/Z790 motherboard resolve this issue, or is there a way to stabilize the current setup further?
  4. Is there any other BIOS tuning or software I should try to fix this?

The main reason I went with Intel over AMD was so that I didnt have to upgrade my mobo, along with availability here in my country. If I do have to buy a new Mobo I'll likely see if I can return the Intel chip to Amazon Australia where I purchased it.

Thanks in advance! 😊