Overclocking CPU, Biostar TP43d2 A7

Hi there,
I'm currently OCing a E6300 with a Biostar TP43D2-A7 motherboard. The problem I've come across is I can't seem to set the cpu voltage. (after tweaking the items in BIOS)

I've gone to desktop and seen my multiplier and my voltage fluctuate. (E6300 stock volt is .8 to 1.3, my voltage fluctuates from 1.184 to 1.296)

Here are some of my BIOS options (copied from another user who had the same issue):

Ratio CMOS Settings
This item allows you to set the CPU ratio frequency

CPU Frequency Setting
This item allows you to select the CPU Frequency
Options Min=100MHz - Max=800MHz

Overclock Retry Count
This item allows you to set the overclock fail retry times.
Options: 3(Default /Min=1 - Max=8

Right now it's on default of 3.

FSB to NorthBridge Latch
This item allows you to select FSB Frequency
Options: Auto (Default) /FSB 800 /FSB1066 /FSB 1333


DRAM Frequency
This item allows you to control the Memory Clock
Options: Auto (Default) /DDR2 533MHz /DDR2 638MHz / DDR2 667MHz / DDR2 800MHz / DDR2 851MHz / DDR2 886MHz / DDR2 1066MHz

On 800MHz

PCIE Clock By
This item allows you to select the PCIE clock control
Options: Auto (Default) / Fixed 100 / Manual


PCIE Frequency Setting
This item allows you to select the PCIE clock control
Options are 100 (Default) / Min=100 - Max=150

on default of 100


VTT Overvoltage
This item allows you to select the FSB Voltage Control
Options: Auto (Default) / +0.025v - +0.700v

No idea what to set this at...???

CPU GTL Ref Voltage
Options: 0.63*VTT (Default) / 0.67*VTT / 0.58*VTT

No idea on this one either...???

Basically I'm just trying to get the lowest stable volt on an OC. (currently 1.86 OCed to 2.3, want to get to 2.5 while not surpassing 1.35v with the auto-voltage thingie)
The manual doesn't explain anything. The only thing it has about overclocking is the software overclock utility.

And it's the 65nm 1.86GHz Core2Duo

My cpu voltage fluctuates from 1.184 to 1.296 when OCed to 2.3GHz...so I'm not sure if this is voltage-auto mode or the result of intel stepspeed?

I'd like it to OC it to 2.5Ghz while staying under 1.296, but when I do, it raises the voltage to 1.36
I said the settings should be explained in the manual.

I never said the manual would explain overclocking. lol

I run my E6300 at 3.45ghz with stock voltage (1.325)

Dont leave it on auto, set it to manual and put it at 1.325v. In fact that cpu has no problem running 3ghz undervoted to 1.25v. So theres no reason to overvolt.

I know that already.

But the problem is there is no way to manually set the cpu voltage in BIOS.

The only voltage that can be changed in BIOS are stuff like overvoltage +5%, +10%, +15%

Basically, there is no where to "directly" change the CPU voltage in BIOS...or am I missing something.
No, when I say auto, I mean I can't change anything - the mobo/programs manage the voltage by itself. I don't mean an "auto/manual" option bar.

Again, the 5%, 10%, 15% is not changing the actual base CPU voltage, but only deals with cpu overvoltage. Since I don't know what the base CPU voltage value is, I have no idea what percentage will be changed if I use the overvoltage option.

I did try to guess-and-test it with auto-overvoltage, 5% overvoltage, 10% overvoltage, but the numbers didn't seem to make a difference when I checked CPU-z
Btw, due to CPU vdroop (which I believe is the difference in voltage between idle and load?)

what is the "set" cpu voltage?

If I set the CPU voltage to 1.3v, or a manual says the max it can take is 1.3v, is this referring to the voltage during idle or during load?

Hard Line

Apr 15, 2008
I have to say that the 45nm e7200 is one of the best overclockers... i got mine running at 4.03 1700 FSB on air using a freezer 7 pro and a biostar TP35D2A7 idles 42 load 63 which is well under the 75C ( voltage is a little high but teps are fne so i don't worry about it