E6750 can't go above fsb@422Mhz

I just can't oc past 422fsb, and I think it's too low for E6750. That's only 3.37Ghz! May Ram can go 1066, I set CPU voltage higher to around 1.5, but it just doesn't want to POST. Of course I have all extra CPU settings disabled except for "bit zero" thing. Followings are info I think is relevant.

Do I need to do anything with NorthBridge config?
Has anyone used same RAM with tighter setting? How?
Should I stick with 1:1 or use make use of RAM's speed?

If I am overseeing any setting, let me know please. My core is extremely energy saving, at 415fsb it can stay under 44 c w/ core voltage 1.27



PSU : 480W
Mobo : Asus P5Q-VM
RAM : G Skill F2-6400CL4D-4GBPK (4-4-4-12, then rest auto)
DRAM voltage (auto)
CPU Cooler : Zalman 9700

OS : windows 7 ultimate


Regards,

Ken

Welcome to the forums.
That board has a big vdrop & vdroop.
Run HWMonitor, Realtemp and a couple of CPU-Z panels showing its speed and rams while running Prime95 sFFT mode and take a screenshot....along with your current setting in bios.

You might need to adjust some NB/FSB parameters to get the FSB higher. Right now you are OCing the whole system, but only adjusting 1 parameter. It's best to focus on 1 part of the system at a time, so you know where the problem is.

I suggest lowering the CPU multi for the time being and focus solely on the FSB. Also keep the RAM speed as low as possible and the timings loose for now. Make sure your RAM is getting it's spec'd voltage (not auto). Play with all your other settings (vNB, FSB Term, NB-GTL, etc...not vcore) until you can boot at a higher FSB speed, and then go from there with your tweaking.

Once your FSB is stable (use large-fft to test) you can then play with higher RAM speeds/tighter timings or move straight to the CPU by upping the multi, and using vcore appropriately.

I built a system for my brother-in-law 2yrs ago that has an E6750 and Abit IP35-E mobo. After a vdroop mod I was able to get it 24/7 stable at 3.8GHz 1.4v (as seen in CPU-Z).

kennyk10 said:

I just can't oc past 422fsb, and I think it's too low for E6750. That's only 3.37Ghz!

Click to expand...

Possibly a chipset FSB wall or you need to loosen the RAM timings.

Hi, thanks for ur replies.
RAM is spec 4-4-4-12, and I have it loosened at 5-5-5-12.
I have tried with 5-5-5-15 already as well, but not good.
How do I break FSB wall? Can I do Besel mod on my e6750?
If yes, which pin in below picture needs to be covered? There are different ways for it, I don't know which is right for e6750!

Ken

Please list all your BIOS settings to get more help. There may be other settings that might help. The BSEL mod might help, but you may have options in the BIOS that allow you to make the same changes w/o doing the mod.

kennyk10 said:

I just can't oc past 422fsb, and I think it's too low for E6750. That's only 3.37Ghz! May Ram can go 1066


RAM : G Skill F2-6400CL4D-4GBPK (4-4-4-12, then rest auto)


Regards,

Ken

Click to expand...

Ken,
That RAM is only 800, not 1066. I am sure it can squeeze more out of it than 844, but you never know. My E6750 has seen 8x448 with OCZ Plat 6400 RAM. I am going to try and get more with better cooling and faster RAM when my Reaper 1066 gets here.

Another thing to try to make see where the problem is - lower your multiplier and try to get the FSB as high as you can.

Edit - also, loosen up the RAM if it is 800 and you are exceeding it.

1:1 is probably as slow as the ram can go, and that's already OCing it. Try loosening it's main timings to 5-5-5-15, that should buy you more OCing room. Most decent 800-4-4-4-12 ram will do 900-950 at 5-5-5-15. My PI-blacks do just south of 1000 at 5-5-5-15.

Most motherboards, it would seem that the "BSEL" mod isn't required.

RJARRRPCGP said:

Most motherboards, it would seem that the "BSEL" mod isn't required.

Click to expand...

If your mobo has FSB strap options then you don't need it. Only the very lowest OC boards can benefit or boards that have no OC options at all.