ASUS P4C800 (-E) Delux : Vtt, Vdimm, Droop & Vagp mods....

[PIRATA!]

Hi!
According at what is written on Malves Corner, the well known mods for this mobo are the Vdimm, the Droop and the Vagp mods.

Can any one tell me something about the Vtt mod and related Vtt check directly on motherboard using a tester??

Can any one tell me if the Vtt does follow the Vdimm even after the Vdimm mod??? I mean... will Vtt be 1/2 of Vdimm even at 2.9 to 3.2 (setted by trimmer)???

Thank you very much.

[Malves]

Yes, VTT will follow vdimm even if the board is modded. Beautiful!

You can check VTT on pin 9 of LM324 - same IC for the Vagp mod.

[PIRATA!]

Are you really shure about that?
So you are saying that the ASUS P4C800 Delux and the P4C800-E Delux are the same in this and they will always have Vtt 1/2 Vdimm ?? Even at 2.9, 3.0, 3.1 and 3.2????

I mean... I set in bios 2.8 and then I toggle the trimmer to rise up Vdimm. You are saying that Vtt will always be 1/2 of REAL Vdimm even if in the bios I have setted up 2.8 ???

About the Vtt check... PIN 9 of LM324 IC is the 9th pin starting round from the pin near the little ° in the corner (that I suppose it be PIN 1) ??

Let me know, please.

Thank you very much!

[Malves]

yes, that's pin 9.

That was my experience when modding a P4C800-E for a costumer. At 2.65 vdimm pin 9 was reading 1.3?v, then i upped the vdimm via trimmer to 3.45v and got a reading on pin 9 of 1.72v. So, i am assuming VTT follows vdimm. I could be wrong, thou. ??

[PIRATA!]

Thank you very much for your reply.
I'll try it in a few days, just the time to get a P4C800 Delux.

P.S.: Are you Malves of Malves Corner ??

Thank you very much again.

[Malves]

Yes, bro.

[PIRATA!]

That little site is well made and really helpful.
Its a really good job.

Why don't you write down a line after the Vdimm mod of P4C800 about the Vtt and related check??
It would be rellay a complete mod page.

P.S.: About the Droop mod... do you think is really necessary for stability?? Do you think that this could affect to a good overclock??

P.P.S.: When you say "Lower the resistance for more volts", you mean to start with the trimmer set to "0" and then to rise up the connection between the two pins ?? I mean... you say to set the output of the trimmer to "0", like if it must not pass through any power, like if the trimmer is not even soldered to the mobo ??

Thank you again.

[Malves]

Some ppl say the droop helped them get better oc. So, it might.

Lower the resistance for more volts, means you'll have to start at maximum resistance for the trimmer (say a 50k ohms resistor set at 50k ohms) and then lower it.

Thanx for the compliment on the site.

[PIRATA!]

Oh... I see...
So I have to start from a resistance of 50k Ohms and then start lowering the resistance going forward to the full pass through of power, right???
At 50k Ohms will the Vdimm be already increased?? If YES, how much??

Thank you again.

[Malves]

No, it won't be increased at 50K. If i remember right, it starts increasing at 47K.

[PIRATA!]

Thank you again.
Last two things.

Using ground on PIN 11 of IC is really important or is it the same if its used a ground point on the mobo, like a hole for a srew???

And for the Droop mod... is 28k Ohm setted before or after soldering??

Thank you very much.

[Malves]

Yes, you can use any ground you want. A screw hole will be fine.

You set the trimmer at 28k before soldering.

[PIRATA!]

Thank you very much.
I'll make these mods asap.
I'll write you back with my impressions.

Thanks again.

[PIRATA!]

Ah!
I forgot to ask you another thing.
SOrry for all these questions, but you seem to be the one that knows good these moddings.

I would like to know if you can tell me how to check the Vchip (Vdd) volgage.
I ask you this because I have read this from the ABIT IC7 – IC7-G – IC7 MAX3 ALL in one Modifications - The way to go!:

.…ABIT and EPOX mobos have dedicated circuitry for the Vchip (Vdd), set at 1.49Volts. On the other hand, the Vchip on ASUS mobos is increased with respect to the VCore of the CPU, so when we select 1.725VCore, the Northy is supplied with 1.725Volts as well…That’s clever from ASUS side…

Checking that voltage I will be able to get two checks in a time: the Vchip and the Vcore.

Please let me know.

Thank you very much again.

[Wizardkt]

Hey Malves

I just did the vdimm mod and I ran into sort of a problem. I set it to 2.55 as all the guides say, but after doing the soldering work I end up losing the 2.55 option.

Not in bios but here are my volts now

2.55=3.06
2.65=3.06
2.75=3.16
2.85=3.26

What happened? Did I fry part of the IC chip? How did I suddenly lose some range? I am using 1016 bios, and I did all my soldering carefully

Also how are you able to get 3.45 out of the 3.3 line for your customer? I thought the absolute max was 3.3 and even that is flaky.

Thanks for any help.

[PIRATA!]

Mmmm... really strange.

I hope not to lose my 2.55v setting in bios because it should be my new 2.85v.

Malves... any suggestions??

[Malves]

Here's part of the pm I sent to Wizardkt:

"Did you use a 50k trimmer? If so, was it set at 50k before you soldered it? If not, no problem, just turn the screw counterclockwise to raise the resistance and lower the vdimm. It works like this...

counterclockwise = raise resistance = less voltage
clockwise = lower resistance = more voltage"

@PIRATA

Never looked for Vchip reading point on the Asus. Sorry!

[PIRATA!]

Thanks any way.

About the trimmer...
If I rise it up to the maximum, it can reach only 47.3K Ohm, and not 50K Ohm.
Is this a problem for the mod??
In any cases, is this normal for a timmer??

Thank you again.

[Wizardkt]

Thanks for the PM Malves. But my problem is not with voltage, it is with the fact that I lost range. I would like to have the full .4 voltage range to play around with. I want my max to be 3.25 but I want my 2.55 setting to be 2.95. Right now my lowest setting with my dmm is 3.05. Both 2.55 and 2.65 show this. I guess it means that I dont have a 2.55 setting or it doesnt work for some reason.

Is it possible that shorting pin 6 with pin 8 would have done this? Im pretty sure that my soldering was ok, but I will check.

If you two guys know what happened that would be great.

[PIRATA!]

This is really strange.
What kind of trimmer are you using??
Didi you solder the right pins??
Have you soldered both PIN 4 & 6 or only PIN 6 to a generic ground of the mobo, like a screw hole or something??

[MkzK]

can u help me with my p4c800 dlx, 2.4m0 and corsair ddr500 i just mod my mb just like malves said at his website but i cant reach even 250 fsb 1:1 with my settings am i ding something wrong ? in the bios i set my ddr voltg to 2.8 vcore 1.6 , fsb 250 and ddr bus 400 it means 1:1 right in turbo mode. at spd i set ddrs to 3-4-4-8 and it doest boot it try to but at windows start it reboot

[LikwidKool]

Originally posted by Wizardkt
Thanks for the PM Malves. But my problem is not with voltage, it is with the fact that I lost range. I would like to have the full .4 voltage range to play around with. I want my max to be 3.25 but I want my 2.55 setting to be 2.95. Right now my lowest setting with my dmm is 3.05. Both 2.55 and 2.65 show this. I guess it means that I dont have a 2.55 setting or it doesnt work for some reason.

Is it possible that shorting pin 6 with pin 8 would have done this? Im pretty sure that my soldering was ok, but I will check.

If you two guys know what happened that would be great.

wizard in my experience the 2.55 was not even functional before vdimm mod. 2.55 unmodded will be 2.65 and when modded 2.55 will be whatever your 2.65 option is.

Strange I know, but thems the brakes.

[eulercdc]

Malves,

What happened to your site: http://www.malvescorner.com/p4c800.htm
I've tried to open it but it didn't!!!

I need the scheme for drop mod and Vdimm mod for the P4C800-E Deluxe!!

Thanks!!

[masterofpuppets]

MalvesCorner is currently down that's why. I have been trying to access since yesterday to print off the p4c800 page and images but to no avail.

[PIRATA!]

Hehe!!
I always save interesting mod pages on my hdd.
You better start to do it too.
Here you go!

Cheers.