beyond 400fsb + 8g not stable

Nov 26, 2005
15,189
401
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UD3R F9bios
8g DDR2 900 @ 4.4.4.12 - tested at 1:1 and is fine
4g DDR2 1000 @ 5.5.5.15 - tested at 1:1 and is also fine
Q9550 chip is 4Ghz stable at 1.34vcore

Since I've had the board, 450fsb has been bugged out. 500fsb will work no problem. I'd like to have the 8g to use with Premiere Pro as the machine will be my NLE editing machine. I know 8g and a quad is a tough mountain to climb. 4g & at 500fsb was relatively easy with my DDR2 1000 kit. 4g & 450fsb with my DDR2 900 modules does not get along. So i figures wth, might as well just put the whole 8g in and keep trying. So far, 400fsb and my Q9550 works great. Even with the memory profile (sub-timings) at the tightest settings (standard, Turbo, & Extreme)

I've raised the PLL, MCH, Vcore, VTT and still cannot dial in 450fsb - I'd be happy with 3.825Ghz as it will be air cooled for a while. What am i missing?

If nothing works, i might piece this out for some net and dive in head-first for another i7. Here's what I've planned if this falls through:

Wow, it just sold out and is on Auto-notify
Will this be good RAM for around 4Ghz?
and as always the MC i7 920 199$ D0
 

elconejito

Senior member
Dec 19, 2007
607
0
76
www.harvsworld.com
I upgraded to F11 from F6 over the weekend. I was totally happy with F6, but I wanted to test out the Spinrite theory (see the spinrite thread wandering around somewhere) with a newer BIOS.

3.8Ghz (425 FSB for me) did not work at anything near my previous voltages. I went there straight from stock as I figured it would be no prob. On a hunch I dialed in 450FSB (4Ghz) at the old settings and with some slight tweaking that seemed to do the trick.

But at first glance it seems like all the old voltage settings are out the window and I'm going to have to go back and OC the hard way again to find optimum settings. You might end up having to do the same
 

Gillbot

Lifer
Jan 11, 2001
28,830
17
81
I've seen FSB "holes" in 775 parts. Many of the 775 gear i've messed with refused to play nice in the 450fsb area so I just avoid it. Shoot for 440 (or lower) or 460 (and higher) and get away from the 450 area and see if that helps. I had one rig that I pumped nearly 1.7v core into trying to get 450fsb running to nno avail, I gave up in frustration and tried 1.3v at 500fsb and it purred like a kitten. No idea why it hated 450 fsb but it just plain refused to run there no matter what I tried.
 
Nov 26, 2005
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Dang, I wish you guys were around right now... I'm seriously considering that mobo but i need more info on that ram and getting to around 4Ghz... i just don't know if the ram is tied to the CPU overclock like on the 775 socket. It seems good... im just afraid if I nee DDR3 1600 it's going to put me higher than I wanted...
 
Nov 26, 2005
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Apparently there are holes. I have 475fsb x 8 3.8Ghz effective, and it seems to be working. just a few min stable into Prime95 full blend and no probs. Opened up the timings to 5.5.5.15, lowered the pll to 1.59v, lowered the vcore to 1.33v, lowered the mch to 1.36v, lowered the termination to 1.30

EDIT: I pulled the trigger too soon on another i7 setup, o well