I7 920 & R2E Uncore stuck @ 3.8GHz

[Dark-Master]

Hello.......

I will keep this short. My 920 Uncore stuck @ 3.8GHz with any kind of settings even all lowest speed but when uncore clock goes 3.8GHz or higher = unstable and when it goes @4.0GHz, my Windows won't boot(instant hard-restart when win logo appears). I tried set IOH to 1.3v, CPU to 1.4V and QPI to 1.5V with 3GHz cpu and 1.6GHz Memory but still no luck?!?!?!?!?.

I'm frustrated with this chip. It needs 1.4V when running @ 4.0GHz or more which is bad for air cooling with Thailand weather(and yes, uncore still stuck @ 3.8GHz).

I was able to get it stable 24/7 @4.0GHz 1.3V. But after I installed GTX295 in this system, max 24/7 full load stable is only 3.8GHz.

Why I want my system to runs @4.0GHz uncore? Because I bought G.Skill Trident 2GHz and with 3.8GHz uncore, it can only run @ 1.6GHz with 200BCLK. I would love to see my memory running @ 2GHz. :(

I'm gonna cry!!!!!!!!!
:ROTF:

sorry for my english

[Kuntz]

You need to increase your VTT to 1.4v or higher. I haven't seen IOH voltage helping my Uncore/NB speeds at all, so leave that at 1.1v until you've tried everything else.

Uncore/NB/IOH On my system under watercooling:
1.375 vtt = 3.8GHz or so
1.525 vtt = 4.2GHz or so

[Kylzer]

Why ?

uncore @ 3.2ghz would be fine and makes not much if any difference.

[Leeghoofd]

I run my rig at 3.8Ghz CPU speed (1.12Vcore), 3.6Gz uncore (1.3QPI) and the rams at 1600mhz C6-7-6-18 1T TRFC 82 and B2B to 4... almost as fast as 2000mhz C7 with B2B 10... , less voltages required for the CPU and QPI... I7 doesn't need high speeds unless you want to bench the crap out of it... for daily use 2000mhz rams are pure show... and many CPU's have a hard time keeping up due to the uncore...

[Sam_oslo]

VVT has alot to say about the stability of the Uncore.

Some CPU-batches have poor IMC and can't run at high Uncore at all, but even those with "capable IMC" may need a very exact value of VVT to run stable at higher speeds. Have you tried different VVT?

[Alexxx650]

http://pic.ipicture.ru/uploads/090905/thumbs/M57rNUvIg3.jpg (http://ipicture.ru/Gallery/Viewfull/23244922.html)
4400 uncore 1.675v - cold water

[Dark-Master]

@ Kylzer, 4.0GHz Uncore is required for 2GHz Memory Data Rate.

@ Sam_oslo and Kuntz, I tried even 1.5 or 1.55 VTT and I will keep trying more. I may have to use watercooling for better overclocking.

@ Leeghoofd, I understand what you said. The reason is that I just want it to run @ 2GHz, it's fine if it doesn't. Thank you for info

@ Alexxx650, Very nice.