2140 overclock

[witty]

i got a e2140 last week, so ive been working on my overclock, right now its running at 2.8ghz at 1.25 volts in the bios. cpuz incorrectly detects it as 1.184 for some reason though, so im not entirely sure what its actually getting. to get to 3ghz stably i need to increase it to 1.35 in the bios, and i tried 8x400 at volts all the way to 1.4 with no luck.

the mobo is a ga-p35-ds3l, memory is running at 440mhz cas 4 without any errors. so its not the ram, its an m0 stepping.

anyhow its a pretty good overclocker, when i get better cooling maybe next week ill try some more volts and see what i can get.

ran it through orthos small fft's and the temps maxed out around 48 degrees. this is on the stock cooler, at 2.8ghz, undervolted. not bad

 

[Evilonigiri]

Congrats

Cpuz pretty much always incorrectly reads the voltage. Some people call it th voltage drop I think.

 

[CompuTronix]

Allow me to clarify...

Vcore is created on the motherboard by the voltage regulators, which are powered from the 4 pin connector near the CPU socket, and is fed from a 12 volt rail in the power supply. Vcore BIOS indicates commanded Vcore, not applied Vcore.

Commanded Vcore is sent from BIOS to the motherboard's Super I/O (Input/Output) chip for Digital to Analog (D to A) conversion, then to the CPU voltage regulators. Applied Vcore output to the CPU socket is monitored by a feedback circuit, which is converted from Analog back to Digital (A to D) again by the Super I/O chip. Applied Vcore can then be displayed in Windows by monitoring software.

There is always a difference between commanded Vcore (Digital), and applied Vcore (Analog) as seen in Windows, which is a result of D to A to D conversions. Further, there is a difference between Vcore Idle, compared to Vcore Load. The voltage drop seen in Windows based utilities (digital) such as CPU-Z or SpeedFan Charts, when observed at Idle, then observed again under Load, is known as "Vdroop", which is typical to power supplies under Load.

Regardless of how well regulated a supply may be, there is always some measurable voltage sag between Idle and Load. The most accurate Vcore readings can be observed by measuring the voltage regulator input to the processor socket using a scientific grade DVM (Digital Volt Meter).

I was motivated to purchase my Asus P5K variant largely because of the "Vcore Damper" feature, which was included in a recent motherboard overclocking review here on Tom's. This feature tightens Vcore Idle to Load sag to as little as .008 volts (8 millivolts), which I've found to be true, and the maximum sag I've observed has been .016 volts (16 millivolts).

This is a fantastic improvement over some motherboards, which can sag as much as .080 volts (80 millivolts) to .100 volts (100 millivolts). The benefit of low Vcore sag is that it allows lower Vcore settings in BIOS, which of course translates into lower temperatures.

As I recall, Vcore inaccuracies that were present in CPU-Z through version 1.37, affected voltages above 1.4 only, which would revert to 1.26 and remain frozen at that value. If a Vcore of less than 1.4 was set, then CPU-Z would display correct Vcore. This was a known problem at the time, and no longer exists through the current version 1.41.

Comp