Overclocking on s1156, pifast higher than pi?

[Calathea]

Hello friends.

 

I have like many others tried on s1156 for hwbot country cup. I'm running a GIGABYTE P55A-UD4 and the Core i3 550 on LittleDevil single stage, ca -55 Celsius. I remember my first encounter with H55M-UD2H and i3 530, it was a fun platform to OC back in the day and I think one of my first to run DICE on.

ANYHOO... I've ran into a problem. I can run Pifast all the way up to 5,66 GHz, 236 bclk, it gives no errors and performance is fine. But as soon as I fire up super pi and start 1M I'm greeted with either black screen or BSOD? WTH? Mobo seems to max out fsb around 240, which I am fine with. After all I think H55M was way easier to clock up bclk with and 240 is decent for most P55 mobos. I've never ever seen pifast go higher than super pi before, what am I doing wrong?

 

Settings were

 

1.7 vcore

1.55 vtt (probably dangerous yes)

1.2 SB

1.7 PLL

 

Max of this chip on SS

[Massman]

My first Clarkdale chip could do 6.6G Wprime (iirc) and only 6.2G Pi 1M. I re-tried a hundred times I think.

 

I know it sounds weird, but just wanted to share this.

[Calathea]

Weird business indeed.Come to think of it I had a 3570k for MOA qualifiers that did wprime above pi too, ruled it down to crap IMC. Is that the case here too maybe.. Moar volts will be tested, when does vtt insta kill?

 

edit: on a second thought I will try some other memory dividers before I kill the chip. Might even run hwbot prime too!

Edited December 16, 2013 by Calathea

[der8auer]

I think it's pretty normal that you can run a higher pifast than 1M. On my Ivy-Bridge CPU I could run about 100 MHz higher PiFast than 1M aswell.

[Calathea]

But pifast is harder than 1M on both cpu and ram no?

 

seems I'm not the only one with i3 s1156... look at Alex@Ro's results on i3 560:

 

http://hwbot.org/submission/2104033_alex_ro_pifast_core_i3_560_16.34_sec

 

http://hwbot.org/submission/2104357_alex_ro_superpi___1m_core_i3_560_7sec_906ms

 

325 MHz less to run 1M.

Edited December 16, 2013 by Calathea