SB Overclocking, results and questions

[andersonviola]

specs:
HAF 912, no extra fans (yet)
ASRock z68 pro3 gen3
i5-2500k
Hyper 212+
G.Skill sniper 1600 1.25v 9-9-9-24
Antec EA-650

This board has voltage adjustments in .05 increments, thus the +50mv, +100mv, etc
all Prime is blend test
PLL overvoltage, power saving mode and spread spectrum are disabled
CPU PLL is at 1.794 on auto
no LLC in BIOS on this mobo

Attempts:
4.3, +0mv, 1.256, 56c max, prime error on 1 core at 6 hours

4.4, +0mv, 1.256, 56c max, prime error after 45 minutes

4.5, +0mv windows won't load
4.5, +50mv, 1.304, 60c, running prime 2+ hours when BSOD (0124)

4.6, +50mv, won't load windows, BSOD (0124 - needs more vcore)
4.6, +100mv, 1.344 at load, max 68c, BSOD after several hours of prime (0124)

4.7, +100mv prime error at 1 hour, max 68c
4.7, +150mv, 1.392, 74c, prime error at 3 hours

stable:
4.4, +50mv, 1.3, 65c, prime stable for 18 hours

4.5, +100mv, 1.344, 70c, prime stable for 14 hours

4.6, +150mv, 1.392, 76c, prime stable for 14 hours

4.8, +200mv, 1.44, 80c, prime stable for 9 hours but alternates between 4800 and 3300?


So, how does this look for a 1st time at OCing? I am thinking of staying at 4.6, 1.39, 76c max, but could also see doing 4.4 with less voltage.

I'm not sure whether this happened on any of the other setups, but at 4.8 I saw in CPU-Z the core speed would fluctuate between 4800 and 3300 constantly. Disregarding for the moment the high temps, is this a wall I am hitting or are there other settings that would fix this (like enabling PLL overvoltage perhaps?)

Thoughts?

 

[aaksheytalwar]

I recommend going down to 4.3-4.3 with lower voltage, will help temps a lot and you won't lose tangible performance.

 

[andersonviola]

I am leaning towards 4.4, 1.3v. The comp is temporarily in the attic, so I think max temps will be closer to 60c when it moves downstairs.

Can anyone tell me why at 4.8 the comp was stable but the multiplier and voltage kept fluctuating between 4.8 and 3.3?

 

[MarkLuvsCS]

Take a look at core power limit, on my asrock z68 extreme3 I had the same problem until I changed this value. It's default is 100 but I set the limit to 200. I think it was under voltage settings.

 

[aaksheytalwar]

Try for 4.3 sub 1.3. I keep 4.3 at 1.28 right now. Med load 50+-c heavy load 55+c. This is with ht on 2600k

H100 tho

 

[andersonviola]

Take a look at core power limit, on my asrock z68 extreme3 I had the same problem until I changed this value. It's default is 100 but I set the limit to 200. I think it was under voltage settings.

under the power limits I set short at 500, long at 500, long duration at 1, and core current limit at 300, all recommendations from

http://www.overclock.net/t/1198504/complete-overclocking-guide-for-sandybridge-asrock-motherboards#