Q9550 overclocking problems

Minty-Linty · 27 Jun 2009 at 12:21

I have overclocked q9550 to 3.4 ghz sync with ram 800 mhz, and all tests fine with prime95. but as soon as i go above this prime95 cuts core 2 out, doesn`t seem to make any difference with any volts to cpu. ANY THOUGHTS ?

Minty-Linty · 27 Jun 2009 at 12:23

I forgot to add, I can get the machine to boot @ 4ghz. and normal operations work ok, but I know that as soon as I stress the cpu`s to 100 % the 2nd core will stop working.

jmc007 · 27 Jun 2009 at 12:38

At it's limit? Have you tried upping the core voltage any?

b.t.w. There is an edit function in case you did not know.

Minty-Linty · 27 Jun 2009 at 12:49

I have tried upping voltage, seem to make no difference

jmc007 · 27 Jun 2009 at 12:53

Maybe give some details of your hardware and settings fsb, mulitiplier, vcore, ram settings and it'll drag someone more informed to help you here.

OzZie · 27 Jun 2009 at 13:20

Could do with knowing:

CPU PPL voltage
FSB Termination
RAM Voltage
RAM frequency/number of sticks of RAM.
RAM timings
Northbridge voltage

I'm assuming most are left on auto?

Minty-Linty · 27 Jun 2009 at 21:49

cpu I have pushed to 1.45
fsb ter 1.5
ram 2.1
timing 6 6 6
ddr ram is ocz 6400
not sure about the other as I have a gigabyte ep45-ds4,
does that help ?

OzZie · 27 Jun 2009 at 21:53

I'd reduce the CPU voltage! Does it report those voltages in CPU-Z?

Realistically you dont want to go over 1.375v on air cooling. 1.4v max.
edited.

Minty-Linty · 27 Jun 2009 at 21:59

ok, any ideas why the 2 core stop working, but the other 3 are good with prime 95 ?

OzZie · 27 Jun 2009 at 22:06

All it means to you and me is that the overclock isnt stable!

Run Intel Burn Test (15 times, max setting) and see if it is ok. That's usually indicative of enough CPU voltage. Errors in prime can be cpu voltage, northbridge voltage, or memory issues.

Providing you have your RAM at its rated speed (or below) with the correct voltage and timings, then you eliminate this factor.

If your northbridge voltage is on auto, set to to 1.30v.

OzZie · 27 Jun 2009 at 22:29

My mistake when i said 1.5v FSB termination. I was refering to the CPU PPL voltage.

FSB Term can be left on auto (maybe called something else in your BIOS)

Minty-Linty · 27 Jun 2009 at 23:26

no its is called FSB termination. thanks. will give it a go

AMG · 27 Jun 2009 at 23:43

I ve got my CPLL set to 1.6 about a volt more than auto but my mobo is famed for over doing stuff

I got mine set at
1.2567 vcore
FSB term 1.4
CPLL 1.6
dram 2.2 (OCZ states that for the mem i have)
NB 1.35
i also knocked up the SB by one knock

also i enabled "vdrop" as my vcore kept flutating

Minty-Linty · 28 Jun 2009 at 18:53

mmm. 3.8 @ 1.2567 is very good, what ram you got