Advice on upping voltage please.

sastusbulbas · 18 Apr 2010 at 13:08

OK so this is my overclock, crashes every so often on games, blue screened on Prime Blend Test quickly.

All voltage options are on Auto. CPU Vcore 1.26250v CPU PLL 1.5v and Dram Voltage 1.8v for example.

As the overclock has only resulted in some game crashes and has been in place since December 09 I am hoping it is simply a case of fine tuning, as voltage options are on Auto I am guessing tweaking voltages may be a good place to start as I am unaware what part of the OC is unstable?

Any opinions or guidlines on what voltage settings etc to tweak and what to avoid?

Here is the OC,

Many thanks

Danm54 · 18 Apr 2010 at 22:23

Check your RAM voltage, DDR2 can require 2.1v

The rest should be ok i think, although you may want to keep an eye on them with stress testing.

Temi_D · 18 Apr 2010 at 22:34

That is very strange for the chip to require 1.3+ volts at that frequency. I had one (before i changed to my Q9650) and it did 3.7GHz at 1.225v but that was at 350FSB and the multiplier set to 10.5

Try 381MHz FSB and setting the multiplier to 10.5 instead of 10 using the same voltage as before (its still gives you 4GHz).

Also Gigabytes boards have very high vdroop which might be affecting your OC. Have you tryes prime95 or intel burn test?

sastusbulbas · 19 Apr 2010 at 08:36

Bios states VID voltage at 1.2625v, as does Core Temp, though CPU-Z states 1.376v? Not sure which is correct.

I tried running the VID at 1.300v in Bios but PC wouldn't boot.

I ran Prime with small FFT's and ended up with an error on one core at 4Ghz, test was not on for hours but it did run then stopped testing that core and continued with the other core, whereas with a general Blend test it would shut down quickly at 4Ghz.

I guess this indicates Memory could be improved? Currently its at stock speeds with stock volts.

Is there any way to check or adjust VDroop? Is the CPU-Z reading changing from 4000.2Mhz to 3999.8Mhz a lot any indication of anything?

I am currently giving 10.5x 381 a go, my memory must still be linked to the CPU overclock as it has changed to 381Mhz. Not sure if this is good or bad?

Edit, the above didn't last, currently on 8.5 x 450 with a 3825.0 OC with an 1800fsb and volts at 1.44v according to CPU-Z. no real change in idle temps at 49*C max. Memory is running at 450Mhz 1.1 5/6/6/21/48/2T

Above has done 5min in Prime but with temps hitting 69*C

Danm54 · 19 Apr 2010 at 22:36

1.44v is a bit over the reconmended.

A Prime95 blend test is a real test of stability, if it passes 8 hours of that you're ok, although some will test for longer.

Have you got Speedstet enabled? This could be the reason for your Mhz change, its usually better to disable this when overclocking.

Memory is linked to your fsb, there is a multiplier you can change to alter this or you could leave it on auto, if you're overclocking your memory id up the voltage to 2.1v, this is usual for DDR2 memory.

VDroop is the drop in voltage between what you set in BIOS and what actually gets to your chip, there is the pencil mod to help with this but on newer boards it's not really a massive drop so it's no biggy.

I don't know how much testing you've done but id suggest manually setting your voltages, CPU 1.376v as you know this is ok for temps, 2.1v for memory, set your memory mulitplier to keep it running at stock speeds and drop back to say 3.6Ghz, run Prime Blend test and see if thats stable, if it passes 8 hours then up to 3.7Ghz, repeat tests, increase overclock etc.

Keep an eye on you memory speeds, its easy to change your fsb and forget about you memory.

Id also advise a good read through here if you haven't already http://forums.overclockers.co.uk/showthread.php?t=17612922

Good luck