Voltage show Error values with 100% C2D load.

[bigspin]

Guys my P5B-E have some issus i think.I'm using latest 1202 bios and I OC E6400 to 354 x 8 .Vcore @ 1.3500.When I run TAT @ 100% v core going down to 1.2600.But system is full stable.I run 3DMark06 and its OK.
I try to set my Vcore AUTO from bios ,After that I run TAT.At that time Vcore not going down and keep at 1.3400 range.Is this Mainboard issue or PSU issue(I'm using ASUS Atlas 550W PSU)

I use SpeedFan & PC Probe to monitor temp .Both show same results.

Sensor Name

Vcore

3.3

+5

+12


Nominal Value

1.31

3.30

5.00

12.00

TAT @ 100% Value


1.34(if i set auto) 1.26(if i set to 1.35)

3.23 (+- 0.02)

4.94 (+- 0.04)

11.93 (+-0.05)

 

[dagoth_ur]

i already forgot the reason of this, however, you shouldnt worry about that. In example, I set core vid to 1,35v in BIOS, for my P4, and the cpu-z shows 1.280, as well as it goes even lower when I put the CPU under load (to 1,26v and less)..The reason of this is that the CPU itself lowers the voltage to lower the amperage, which leads to lower heat dissipation..I think I've read it somewhere but Im not sure..So I'll bookmark this thread and wait for some explanation as well as you do 🙂

 

[aoe]

Firstly, it's not unusual when setting a specific voltage for the FSB that the reported voltage is different. I can't offer a good explanation for this, nor can I say whether the sensors reporting the voltage are more/less accurate than the voltage you set in BIOS. However, this is nothing to worry about. Every motherboard I've ever owned shows the same behaviour. What I have noticed, though, is that the difference between the set voltage and the reported voltage tends to be constant.

Regarding the drop in voltage when your system is under load, this is not unusual if the voltage is on the limit for the CPU requirements. When you see this behaviour, the CPU is trying to draw more power, and it's an indication that the voltage may need to be increased. If the system is stable and the voltage drop is minimal (within +/- 0.100V as recommended in the overclocking guide stickied in this forum), then it's nothing to worry about. If the drop is greater, then you should expect potential system instability and consider increasing the voltage a bit more (if that's an option).

When set to Auto in BIOS, it's most likely that the BIOS is automatically increasing the voltage when under load in Auto mode, so that the reported voltage does not drop (you would need to post your voltages at idle to confirm this).

 

[dagoth_ur]

actually, the point is that the voltage is Decreasing under load

 

[bigspin]

Firstly, it's not unusual when setting a specific voltage for the FSB that the reported voltage is different. I can't offer a good explanation for this, nor can I say whether the sensors reporting the voltage are more/less accurate than the voltage you set in BIOS. However, this is nothing to worry about. Every motherboard I've ever owned shows the same behaviour. What I have noticed, though, is that the difference between the set voltage and the reported voltage tends to be constant.

Regarding the drop in voltage when your system is under load, this is not unusual if the voltage is on the limit for the CPU requirements. When you see this behaviour, the CPU is trying to draw more power, and it's an indication that the voltage may need to be increased. If the system is stable and the voltage drop is minimal (within +/- 0.100V as recommended in the overclocking guide stickied in this forum), then it's nothing to worry about. If the drop is greater, then you should expect potential system instability and consider increasing the voltage a bit more (if that's an option).

When set to Auto in BIOS, it's most likely that the BIOS is automatically increasing the voltage when under load in Auto mode, so that the reported voltage does not drop (you would need to post your voltages at idle to confirm this).

My Idle load is 1.35v but under load its show 1.26v
I use SpeedFan to collect my voltage data.System is full stable under TAT 100% load with 1.26v(According to SpeedFan)
I try 3DMark 06 CPU test Its very stable & I got 2440 Marks for CPU.
SuperPI 1M 20.506 sec

 

[T8RR8R]

Mine actually increases in voltage from 1.26@idle to 1.35@load. It all has to do with speed stepping and C1E, basically anything that is supposed to save you energy.