Haswell advice
- Thread starter GR63
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Answers will be at least partly arbitrary and subjective, including mine. And usually temps will dictate the voltage question anyway. Haven't killed a chip or motherboard since 2013 so here goes:
Go with 1.3v manual if Cinebench R20 temps are under 80C.
Don't use BCLK overclocking. That's what will affect other stuff like RAM, drives, GPU.
Only gotcha is that if you don't set a manual/fixed OC then any programs (including some games now) that use AVX instructions will pump anything from 0.05 to 0.1v extra, and you don't really want to exceed 1.3v max for 24/7 on air, imo. Brief benchmarks up to 1.4v is fine (if your cooler could handle it). I believe the max Vcore Intel once stated is 1.5v. However that will degrade your chip faster and air cooling won't cut it anyway. If you leave C-States enabled, it will consume less power when idling even though the speed-stepping is disabled.
Other than that, note that some Z97 motherboards use more LLC by default (Asus springs to mind), so lowering LLC can help with heat and longevity even though it can help with stability. Personally I like to lower LLC all the way, or use the straight line value some boards have, i.e. no raising no lowering. And just find the Vcore value a 24/7 overclock needs.
And don't exceed much over 1.2v for the Ring/Cache/Uncore. I like keeping it to within 300Mhz of the CPU if possible, based on what was said by others who know more than I do (also it helps cut down heat). But after finding the max CPU overclock first.
Go with 1.3v manual if Cinebench R20 temps are under 80C.
Don't use BCLK overclocking. That's what will affect other stuff like RAM, drives, GPU.
Only gotcha is that if you don't set a manual/fixed OC then any programs (including some games now) that use AVX instructions will pump anything from 0.05 to 0.1v extra, and you don't really want to exceed 1.3v max for 24/7 on air, imo. Brief benchmarks up to 1.4v is fine (if your cooler could handle it). I believe the max Vcore Intel once stated is 1.5v. However that will degrade your chip faster and air cooling won't cut it anyway. If you leave C-States enabled, it will consume less power when idling even though the speed-stepping is disabled.
Other than that, note that some Z97 motherboards use more LLC by default (Asus springs to mind), so lowering LLC can help with heat and longevity even though it can help with stability. Personally I like to lower LLC all the way, or use the straight line value some boards have, i.e. no raising no lowering. And just find the Vcore value a 24/7 overclock needs.
And don't exceed much over 1.2v for the Ring/Cache/Uncore. I like keeping it to within 300Mhz of the CPU if possible, based on what was said by others who know more than I do (also it helps cut down heat). But after finding the max CPU overclock first.
ring/uncore @ 3.5ghz is more than enough. any higher doesn't net much benefit and only increases voltages and heat (and by extension, can affect stability/max clocks)
also if there's AVX offset (not all boards will have this), best to set this at -2, to offset the extra power that AVX uses/heat that AVX produces
also if there's AVX offset (not all boards will have this), best to set this at -2, to offset the extra power that AVX uses/heat that AVX produces
Thanks. OP tips were really good and took me back to the day when I had Haswell originally. My chip was totally happy at 4.4 but 4.5 was less happy.
The @tamzzy tip on unCore might help since I set it to 4ghz - no AVX offset in BIOS.
The @tamzzy tip on unCore might help since I set it to 4ghz - no AVX offset in BIOS.
