Motherboards that vdroop the least?

[GFORCE100]

Hi all,

Which 975X/965P chipset motherboards have the lowest vdroop?

I've done some testing on the P5W DH and noticed in Prime95, that depending how many instances I startup (1 instance of Prime95 per 1 core), the system can remain stable on a lower Vcore, than on 3-4 instances of Prime95. Looking closer I noticed it's because the vdroop is smaller. On 1 instance of Prime95, it's about 0.02-0.03 but on 4 instances of Prime95, it's 0.05V. I tested this using a QX6700.

While it's achievable to overcome the vdroop mishapenings with a higher Vcore, this produces immense heat (10C or more).

I'm sure some motherboards out there have some smaller Vdroops. Would you know of any? I heard the P5W DH can be vdroop modded too, but I'm not into soldering enough to do a fine job of it, and can't think of anyone in my area who would do it for me, for a price of course.

Thanks,

[hot_fifty]

have you measured the vdroop or just software reading. I have a P5B Deluxe. It does not vcore, but vraise and software shows the vdroop...

[GFORCE100]

It does not vcore, but vraise and software shows the vdroop...

What do you mean? So in the BIOS you set say 1.40V and in reality this is say 1.425V but software shows it as less?

On the P5W if I set 1.4750V software reports 1.44V (Idle).

[before]

AFAIK bios setting, and software reading are both wrong. :) You have to measure with a DMM on the motherboard in order to read voltage precisely.

To my knowledge, Asus motherboards usually undervolt almost everything. For instance, on one of my P5B, 1.37Vcore bios monitoring (same as software monitoring) corresponds to about 1.32V real voltage as shown by DMM.

Anyway, you may wish to pm a mod for having your thread moved, or post your question again into the Intel section of the forums. I guess you'll have more answers there :)

[crotale]

Some comments on droop:

- There are some thoughts regarding droop that it is only due to bad design of the motherboard. This is not the case. Intel actually states a recommended droop, or "load line", for their CPUs.

- Droop can be worse than what Intel states due to design glitches, but in that case, modding it to have zero droop can make the regulation circuitry very hysteric, and very stressful on the components.

- To measure droop correctly, it's necessary to use a multimeter and to measure the voltage close to the CPU, after as many filtering stages as possible, _and_ with a correct ground. Just using a molex might not be sufficient, since many boards today have a kind of floating ground plane.

- Software is in most cases completely useless, and especially when we are talking about voltages around milli volts.

- Droop is by definition the real voltage from idle to load, measured by a multimeter. It has nothing to do with what voltage is set in BIOS. Each of these settings are just mappings to a value given to the vreg IC.

In my book, any measured droop less than 30mV is healthy for the motherboard. I have had numerous issues when trying to reach zero droop, and if I have to mod a board, I usually settle for 20mV of droop.