P4C800 poly mod

[pfrcom]

I can't find KC8ADU's post with the recipe for the poly mod he did on a P4C800

Has someone got it bookmarked by any chance ?

[retiredcaps]

Re: P4C800 poly mod

I find sometimes the internal search engine here produces unexpected results so I use google and type in

kc8adu p4c800

Then I click more results from badcaps.net

[Toasty]

Re: P4C800 poly mod

Non existent. Been looking for over 1-1/2 years. There was a server glitch a long time ago and I think it went at that time.

Best to cook up your own mod.

There's also a Japanese site that was aimed at overclocking, but has a lot of the poly mod info:
http://www.finetune.jp/~lyuka/interests/pc/p4c800e.html

I'm looking for anyone that has the other 2 FET's, near the CPU, on their board. There are some boards with 2 and 2, but the Japanese mod adds the other one to each making it 3 and 3. They don't say which number it is. It is a duplicate of one in each group that is already there. Willawake had a board that had all 3 in both places, but the photo isn't clear or large enough to make out the numbers. Plus it was over 4 years ago.

I believe I actually have most of the caps to do mine. Now to find them...

Toast

[pfrcom]

Re: P4C800 poly mod

With inspiration from retiredcaps, I found what I was looking for

It's in the "Cleaning Motherboards - ATTN SMOKERS" thread - the one thread I didn't go through, before my original post

You can find it by doing a Search for "P4C 800" (including the double quotes and the space in the middle) - it's post no. 50 on page 3

[Toasty]

Re: P4C800 poly mod

That doesn't cover the other small caps like the Japan site does, nor the VRM in.

Cook your own.

And do all those little 1000@6.3v ones too. I'm using HM's for those.

[pfrcom]

Re: P4C800 poly mod

I'm looking for anyone that has the other 2 FET's, near the CPU, on their board.

Does that mean I've hit the jackpot with two recently acquired boards ?

Refer pics - both have 3 FETs in 3 groups around the CPU, whereas my other P4C800-E has 2 FETs and a blank pad in corresponding areas

Both boards work, but I was thinking of expunging OSTs from the VRM and all 1000uf 6.3v Ltec's

[Toasty]

Re: P4C800 poly mod

Could you re-take the second shot and/or report the numbers of any of the groups. I can't make out the other numbers for the dust or shaking. Little too much coffee today?

I was mistaken. There are 3 of these used. The 2 you have pictured, and another on the RAM side of the CPU.

Unfortunately, the 70T03H MOSFET is no longer available. Best bet will probably be salvage from dead boards. I have the Asus A7VBX-MX which uses 4 of them. That does 1 board for me, with 1 piece left over. I have not investigated a cross reference, yet.

It's not a big deal, as they've been working many years with just the 3 pairs.

Toast

[Toasty]

Re: P4C800 poly mod

Here's my list:

20 - 1000/6.3 - 8x12 - OST-RLS ==== Nichicon HM
 5 - 100/16 - 5x11 - OST-GSC ==== Panasonic FR
 4 - 1200/16 - 10x20 - UCC-KZE ==== Nichicon HZ/HN/HM or Rubycon MCZ/MBZ
 7 - 1500/6.3 - 8x20 - OST-RLZ ==== (10) Fujitsu 820/2.5 - 8x12 Bumble Bees 
  - Adding 1 piece SEPC 560/4v cap at RAM slots in CE108 position. 
   680uF could also be used here.

Once I cross-ref and source the MLCC's for the socket, I will do 1 of the boards, just for my own satisfaction. :)

Do remember that on Asus boards, the white is (+) positive.

Toast

[pfrcom]

Re: P4C800 poly mod

Little too much coffee today?

No, it was the excitement

Here's my report:

Right of CPU are Q208, Q209 & Q210

Above CPU are Q199, Q201 & Q202

Below CPU are Q193, Q195 & Q196

On the three FET models:

Q193 = Q199 = Q208 = 60T03H
................................438086

Q195 = Q201 = Q210 = 06N03LA
................................DT429

Q196 = Q202 = Q209 = 70T03H
................................436336

On the two FET model:

Q193 = Q199 = Q208 = MRC
................................D38NH
................................02L
................................301347

Q195 = Q201 = Q210 = D0324
................................FDD
................................6606

Q196 = Q202 = Q209 = Empty

[kc8adu]

Re: P4C800 poly mod

i will email the guy i did the last one for.he is on a bus to new mexico right now.i am sure he will take some pics for us.

[Toasty]

Re: P4C800 poly mod

I'm having difficulty locating a -reasonably priced- MLCC in 47uF @ 16v.

Dimensions: L: 6.2 ±0.4 // W: 4.9 ±0.2 // H: 3.5

Anyone got a source that's <$5 or $6 each?? I need 4.

I could go to 3 - 33uF or even 4 - 27uF....

-but-

Need to be within the following:
~100uF
L: cannot exceed 6.7mm
L: cannot be less than 5.4mm
W: cannot exceed 11mm mounted side-by-side
H: limited to 3.5mm

Toast

[mockingbird]

Re: P4C800 poly mod

I've seen several, but they're too short. Why are you so picky with the dimensions? Just use a blob of solder or attach some leads. At Digikey, I saw something called "Leaded MLCC".

[Toasty]

Re: P4C800 poly mod

Because it's right under the CPU. No wires allowed, no space to fit. 3.5mm max height.

[Pyr0Beast]

Re: P4C800 poly mod

These are used for tantalums.

[Toasty]

Re: P4C800 poly mod

Tantalum's may be a possibility. But getting the right size and a low ESR is a pickle. Lowest I can find (that fits) is 35mΩ at nearly $4 each...

...and those are about 1mm too tall.

[Pyr0Beast]

Re: P4C800 poly mod

Oh yeah )
Incredibly expensive
Salvage them from a dead graphic card. 8800 series had plenty of them.

[gilly]

Re: P4C800 poly mod

hello
my P4C800 is dead psu cks good unpluged, but in ps fan turns for around .5sec
row of caps near cpu mesures 9 ohms
shorted?
how do i find the shorted one short of taking all out?
thanks for any help

[Toasty]

Re: P4C800 poly mod

Any bulged caps on mobo? If yes, then replace all caps in that bank.

Your PSU may be failing under load. Open and investigate for bad caps. What PSU make/model are you using?

Substitute another PSU if possible.

>>row of caps near cpu mesures 9 ohms<<

Using what for testing? Ohmmeter? Not a valid test. Cap test needs an ESR meter.

You can not test VRM filter caps on mobo as they are in parallel with each other. One good in a bank and others failed will still show as good.

T

[Tomcatciller]

Re: P4C800 poly mod

Just a little question regarding poly caps on this board.

Are they just improving life time, or do they also improve voltage stability of the board and so improve the overclocking ability?

Atm I am recapping my Enermax Liberty ELT500AWT for better voltage stability. Atm I have a stock P4C800E dlx Board with all Rubycon caps close to the cpu socket.

I want to increase OC ability of my P4 EE 3400 Gallatin CPU. The problem is vdrop here. I just try to vdrop mod another board but fail and destroyed it due to lack of tools and knowledge to do such things. So now I should try to recap my P4C800 with polys to decrease that Vdrop just a little bit, or will this not help? I know vdrop is a planed Intel feature to prevent the cpu from self-destruction when going from load to idle, but atm on my board is just too much. It drops from 1,690 V Idle (Bios set to 1,7 Vcore) to 1,504 V under load. When running Prime95 to validate stability of my OC setting it even drops to 1,488 V. And in exactly these moments the test put one core out with failures. So the cpu would run fine with a stable 1,55 V Vcore which is ironically the exact factory VID voltage of this CPU....

So it would be no over volting, just put these evil vdrop away....

Greets

TCC

[kc8adu]

Re: P4C800 poly mod

i doubt it will change vdrop.
as for polymod you will have to do what i did.power up,flip board,and measure voltage at each cap.most will be replaced by 820@2.5.
looks like my original was lost in a server brainfart.