Asus P4C800-E VCore Voltage Variances Revealed

I've completed my testing on the fluctuations of the VCore voltages on the P4C800-E Deluxe and it revealed some very interesting data.

Here is what they did, and I can tell you by looking at this data that it wasn't a mistake that the Asus P4C800-E Deluxe has this broad range of VCore values despite you setting it to a specific Value!! They engineered in a range of .096 for most all settings with this motherboard.

What does that really mean? Well if you set your VCore to 1.6 for example, it's actually going to have a range of 1.648 to 1.552 which is a .048 above and below the set 1.6!!! This is the only voltage setting however that I tested that had an even split of the voltage range!!

Also, when you set it to 1.6 for example, it doesn't set you to 1.6 at idle, it sets you to the high end of the range, in this case 1.648! I believe the reason they did this was so that when your doing things that put the machine under load, it meant that you were getting closer to your 1.6 setting while doing work, but under heavy load you drop to the low end of the voltage range, in this case 1.552. This scenario is true for ALL the settings I tested!!

The other interesing point about this testing I did is that if you go anything above 1.6 in the VCore, your wasting your time and it in fact drops you below .096 range. So instead of having a .048 value above what you set your vcore to, you'll actually get something below the vcore value range ALWAYS!! Which basically means, you'll get a highter vcore range below a 1.6 vcore than you will if you set it to 1.625 for example.

I hope you find this data as useful as I have gathering it. There is clearly a good place to set your VCore to and a point where your actually setting it lower by picking a higher value!! Asus really needs to fix this problem if they are ever going to be taken seriously, at least from an engineering and OverClocking point of view as I do.

Here is a link to the data I discovered showing all the voltages while at Idle and under load for the VCore settings of 1.525 - 1.65.

I found this data to be super beneficial in understanding what's going on under the hood of this motherboard and it's VCore settings.

P4C800-E Deluxe VCore Settings Revealed

........I disagree. I can not use 1.62v or 1.65v. When 1.67v is set it idles at 1.71v and around 1.6v idle.........

Thumper said:

........I disagree. I can not use 1.62v or 1.65v. When 1.67v is set it idles at 1.71v and around 1.6v idle.........

Click to expand...

LOL, well it doesn't matter if you agree or not. Many, Many others complain about this very same issue and see the very same data.

What we need is for people to provide their data that can help determine why this is so on so many of these P4C800-E's.

Let me ask you this, Do you have PM (Performance Mode) set to Turbo? Are you running with PAM/PAT enabled?

I was thinking about this last night and I suspect that having PM set to Turbo may be one of the reasons why the VCore ranges are so wide (.096) so I'm going to be re-testing this with PM set to Auto/Off and see what kind of information this can glean.

Catch ya later!

BTW, I see you're running 5:4 that could be the other reason. These tests were done at 1:1 Heck the combinations are endless.

Xeon said:

What we need is for people to provide their data that can help determine why this is so on so many of these P4C800-E's.

Let me ask you this, Do you have PM (Performance Mode) set to Turbo? Are you running with PAM/PAT enabled?

Click to expand...

......yes it's 5:4, Turbo, and PM Enabled and PAT enabled. If you want me to run any tests for ya just let me know...........

Xeon said:

Many, Many others complain about this very same issue and see the very same data.

Click to expand...

......I have never seen anyone with this mobo that cannot run 1.67v and over but will keep that in mind............

Thumper said:

......I have never seen anyone with this mobo that cannot run 1.67v and over but will keep that in mind............

Click to expand...

I'm not sure what you mean here. I've never stated that I couldn't run at a VCore setting of 1.67v. That's not the issue.

The issue is that the VCore settings on this motherboard fluctuate from what you set it to in the bios of a range of .096 volts no matter what you set it to in the BIOS.

If you look at the data within the link it shows the fluctuations from Idle and under Load.

Hope this helps.

How far above the 1.6 setting does this hold true? I've got a P4P800, but if you want more test data pm me specifics.

GD

Grandpa Dan said:

How far above the 1.6 setting does this hold true? I've got a P4P800, but if you want more test data pm me specifics.

GD

Click to expand...

Thanks Grandpa Dan!

I only tested up to 1.65 in this round of testing which is shown HERE but what I found really interesting is that on the P4C800-E once you go over 1.6 volts this board undervots heavily.

A User from another forum tested his P4C800 (NON -E) and his voltages were much more stable with a Vcore range of on .048 between Idle and Load shown below:

Here is what my vcore variations show?
I verified them with MBM, CPU_Z and Asus Probe.

BIOS Setting . . . . Reading fluxuation in WinXP (Full Load)
1.600v . . . . . . . . . . . . 1.520v - 1.536v
1.675v . . . . . . . . . . . . 1.616v - 1.632v

BIOS Setting . . . . Reading Hardware Monitor BIOS (Idle)
1.600v . . . . . . . . . . . . 1.552v - 1.568v
1.675v . . . . . . . . . . . . 1.632v - 1.648v

Click to expand...

As you can see here these Vcore fluctuations are much tighter than was is occurring for many users on the P4C800-E.

I really appreciate your willingness to help out Grandpa Dan, but I suspect we would probably see something much different with the P4P800 than we do on the P4C800-E since even the P4C800 (NON -E) above has proven to be much better than the -E version of the same board.

Have you tested your board already and know the VCore ranges it produces? If so, then it might be another good base of data to look at, if not I probably wouldn't go through the trouble of testing it unless your so inclined.

Here is how I tested it on the P4C800-E:
-Set the BIOS to each VCore setting starting at 1.525
-Boot into Windows
-Launch CPU-Z and Asus Probe
-Let sit Idle for 3 Minutes.
-Start Taking Readings from CPU-Z and Asus Probe for 3 Minutes.
-Record all Voltages witnessed making note of the Voltage held the longest.
-Launch Two Instances of Prime95 (one normally the next one from the command line) *This is so it puts a full load on the OS since it's Hyper Threading it's the only way you can really do that*
-Record all Voltages witnessed while under load for 3 minutes, noting the one voltage held the longest.
-Reboot and set the next VCore Setting and repeat the steps above.

A takes a great deal of time to do this and it's also why I published my results so that others could get something out of it as well without having to go through it all if they weren't up to the task.

Hope this helps.

Xeon said:

I'm not sure what you mean here.

Click to expand...

......I am not sure either. I really shouldn't post first thing after waking up .........

......I ran the test like you said and this is what I found:


Here is what my vcore variations show?
I verified them with MBM, CPU_Z and Asus Probe.

BIOS Setting . . . . Reading fluxuation in WinXP (Full Load)
1.600v . . . . . . . . . . . . 1.538v - 1.56v
1.675v . . . . . . . . . . . . 1.55v - 1.618v
1.70v............................1.58v - 1.62v

BIOS Setting . . . . Reading Hardware Monitor BIOS (Idle)
1.600v . . . . . . . . . . . . 1.62v - 1.64v
1.675v . . . . . . . . . . . . 1.67v - 1.68v
1.70v............................1.70v - 1.71v

Thumper said:

......I am not sure either. I really shouldn't post first thing after waking up .........

......I ran the test like you said and this is what I found:


Here is what my vcore variations show?
I verified them with MBM, CPU_Z and Asus Probe.

BIOS Setting . . . . Reading fluxuation in WinXP (Full Load)
1.600v . . . . . . . . . . . . 1.538v - 1.56v
1.675v . . . . . . . . . . . . 1.55v - 1.618v
1.70v............................1.58v - 1.62v

BIOS Setting . . . . Reading Hardware Monitor BIOS (Idle)
1.600v . . . . . . . . . . . . 1.62v - 1.64v
1.675v . . . . . . . . . . . . 1.67v - 1.68v
1.70v............................1.70v - 1.71v

Click to expand...

Excellent!!

So for your 1.7 setting it's showing a total range of .13 !! (i.e. 1.58 - 1.71 = .13)

Thanks for your feedback! It shows exactly the same kind of off the wall VCore variances.

Hey, just noticed your right down the road(20 min.).

Quick but interesting prelim.
As you said there are way too many variables to make this easy.

That said:
P4P800 Dlx, volt modded.
282 fsb, mam/turbo enabled.
Mem. 5:4, 2-2-2-6, 3.05v.
vcore @ 1.5875 in bios.

Asus probe & cpu-z readings mirrored each other.
vcore high idle = 1.616
vcore @ load = 1.52
Diff.(range) = 0.96


Hmmmnn???
mere coincidence?

Ahh yes, I see your in Intel's backyard....... SO AM I !!

Quick but interesting prelim.
As you said there are way too many variables to make this easy.

That said:
P4P800 Dlx, volt modded.
282 fsb, mam/turbo enabled.
Mem. 5:4, 2-2-2-6, 3.05v.
vcore @ 1.5875 in bios.

Asus probe & cpu-z readings mirrored each other.
vcore high idle = 1.616
vcore @ load = 1.52
Diff.(range) = 0.96


Hmmmnn???
mere coincidence?

Click to expand...

Wow, I can't believe it!! I would have never thought your P4P800 would even come close to having this range in the VCore! I've never owned your particular board but from what I've seen and understand it's one of the better Asus boards. You're seeing the same exact range as in this Motherboard with the .096 !! Unbelievable!

Thank you very much for testing this, even if it's just this one setting I think it's safe to say that the others won't be much different than what I discovered with my P4C800-E now that you've posted your findings. In fact here is my data for that VCore Setting

BIOS Setting . . . . Reading fluxuation in WinXP (Full Load)
1.5875 . . . . . . . . . . . . 1.536

BIOS Setting . . . . Reading Hardware Monitor BIOS (Idle)
1.5875 . . . . . . . . . . . . 1.632

Total VCore Range . . . . . . . . .096

Thanks again for posting, I think it's becoming very clear here that Asus has purposely done this with their VCore. It makes me wonder however, what the other MB manufacturers are actually doing here.

It almost makes setting your VCore a waist of time when you see this kind of fluctuation, yes it gives differing ranges but what good is that?

compensating for poor psu's. a generic fit so to speak.

Do you really think it's your PSU?

I'm running a tight PSU, a PC Power & Cooling Turbo Cool 510 and it's solid. Gauranteed less than a 1% variance on the unit I'm running. So I'm not sure what to think.

Not my psu. Asus is volt. averaging. Reduce the sharp peaks and valleys creating a smoother wave....less errors...one size fits all. I'd be willing to bet all current asus boards use that range.

Your theory is proving somewhat accurate, however if you look at one of my posts above you can see that there is a user with a P4C800 (NON -E) that has a range of .048 which is half of what yours and mine is. In fact on one of his settings he's only seeing a .032 range which is much better. Not perfect but much better.

Hopefully we can get others to do this test and see what kind of results across more MB may yield.

Thanks for your help Grandpa Dan!

BTW, it's good to know there are other OCer's right here in my backyard!

Not following you re: other post. The way I'm reading those #'s things are matching.

Regardless, here's a little more.
288 FSB, 5:4, 2-3-2-6 @ 3.05v.
vcore = 1.60 in bios
Idle = 1.632
Load= 1.536

It was this one right here:

Here is what my vcore variations show?
I verified them with MBM, CPU_Z and Asus Probe.

BIOS Setting . . . . Reading fluxuation in WinXP (Full Load)
1.600v . . . . . . . . . . . . 1.520v - 1.536v
1.675v . . . . . . . . . . . . 1.616v - 1.632v

BIOS Setting . . . . Reading Hardware Monitor BIOS (Idle)
1.600v . . . . . . . . . . . . 1.552v - 1.568v
1.675v . . . . . . . . . . . . 1.632v - 1.648v

Click to expand...

Talk to you soon.

Thumper said:

......I am not sure either. I really shouldn't post first thing after waking up .........

......I ran the test like you said and this is what I found:


Here is what my vcore variations show?
I verified them with MBM, CPU_Z and Asus Probe.

BIOS Setting . . . . Reading fluxuation in WinXP (Full Load)
1.600v . . . . . . . . . . . . 1.538v - 1.56v
1.675v . . . . . . . . . . . . 1.55v - 1.618v
1.70v............................1.58v - 1.62v

BIOS Setting . . . . Reading Hardware Monitor BIOS (Idle)
1.600v . . . . . . . . . . . . 1.62v - 1.64v
1.675v . . . . . . . . . . . . 1.67v - 1.68v
1.70v............................1.70v - 1.71v

Click to expand...

check his revision.

That was Thumper's results.

My original post was from another guy on a different forum and his are within .048 for 1.6 and then even tighter for the other setting he posted.

So it makes me wonder what's different about his P4C800 (NON -E) that makes his the exception to the rule.

You can find his original post here, his nick is jhites:

VCore Variances on P4C800 (NON -E)