switched from 2500k to 2600k, memory unstable

[Jasonaaronfox]

Motherboard: P8z77-I
CPU: Intel Core I7 2600K, 4.5ghz stable @ 1.35v
Memory: Corsair Vengeance 16GB (2x8gb) rated for 11, 13, 13, 31 2400mhz 1.65v

Before I was running a 2500K cpu @ 4.5ghz 1.32v and the memory worked fine at 2133mhz 1.65v. Now, not so much. Intelburntest craps out every time I set the memory above 1600mhz.

Any suggestions?

 

[Woomack]

These CPUs have weak IMC. It will run at max 2133 and it's not guaranteed it won't degrade over time. Check it at some more relaxed timings or bump voltages a bit.

 

[Jasonaaronfox]

Thank you Woomack. Would I be better off to run it at 1600mhz and shoot for tighter timings? I don’t want to stress the cpu more than necessary.

 

[Woomack]

Try 1600 9-9-9 or 1866 9-10-10 1.50-1.65V, no idea how this memory works on your motherboard.

 

[Jasonaaronfox]

Try 1600 9-9-9 or 1866 9-10-10 1.50-1.65V, no idea how this memory works on your motherboard.

The 1600 9-9-9 works well. 1866 gives kernel error or just doesn’t boot. 2133 11-13-13-31 boots but fails memory testing.

Perhaps I will shoot for 1600 8-8-8 next.

Thanks.

 

[Jasonaaronfox]

Ended up stable at 4.4ghz 1.35v, running the ram at 1600mhz with 8-9-9-24 timing. Works for me! Thanks for the advice.

 

[UltraTaco]

Do you have any benchmarks of before(2500) vs after(2600)? I'd be interested to see if improvement was greatly hindered by lower ram speed?

 

[Jasonaaronfox]

Do you have any benchmarks of before(2500) vs after(2600)? I'd be interested to see if improvement was greatly hindered by lower ram speed?

I would need to run intelburntest with hyperthreading disabled, but that sort of defeats the purpose. I wanted the 2600 for the extra threads. Before Iwas at 2133mhz with 11 cas, now 1600mhz with 8 cas. Access time is almost identical. CAS/(frequency/2)*1000 gives access times of 10.314 nanoseconds before the upgrade and 10 nanoseconds afterward.

At least regarding game performance I saw a jump of 5-10 fps minimum in the two games I have loaded on my system right now. (Heavily modified Skyrim SE with ENB and a game called Overload.)

 

[Jasonaaronfox]

One note, this 2600k chip seems to run a lot hotter than a 2500k. I was hard stuck at 1.35v @4.4ghz and couldn’t go higher with the H60 AIO regardless of how high I set my fan (and my fan can do 260cfm!!!) I suspect an h100 would have performed better, but I don’t have the space for that in a mini-itx case. I chose to instead throttle it down to 4.3ghz and now I can lower the cpu voltage and am seeing a drop of nearly 10C under load. Much more manageable without setting my fans above 35 decibels when gaming.

 

[UltraTaco]

Hyperthreading drives temps up (and required vcore)