Asus P4C800-E Deluxe rejuvenation

[pfrcom]

This P4C800-E Deluxe is built around Intel's Canterwood chipset, the best of its era, and presumably the most expensive

Does the P4C800-E Deluxe use capacitors of similar calibre for a top-of-the-line board ?

Errr no

1500uf 6.3v VRM caps are Elite - not what their name implies

All 1000uf 6.3v capacitors are Ltec, a regular contestant for bad caps (dis)honour awards

And not to be outdone in the race to the bottom, the small 100uf 16v non-vented capacitors are GSC, arguably the worst of the worst

This board has four problems:

1. All fan headers are dead - fans connected to any of them, don't work

2. On-board sound is detected, but produces nothing - it's not missing jumpers on the FP_AUDIO connector, been caught with that before

3. BIOS Hardware Monitor says zero for 12v

4. Drains a CMOS battery fairly quickly

Are any of these problems likely to be caused by bad capacitors ?

I'm loath to spend time and money replacing them, only to end up with something no better than before I started

[PCBONEZ]

Re: Trust Asus P4 boards - no way

Are any of these problems likely to be caused by bad capacitors ?

All of them can be.

If the MOSFETs and chipset look okay I would give it a go.

Try changing just the Elite first and check for improvement.
.

[pfrcom]

Re: Trust Asus P4 boards - no way

I replaced all 7 Elites in the VRM with new Panasonic FJs

All four problems remain

For "MOSFETs and chipset look okay" is a visual check adequate, and/or the fact that the board works perfectly apart from the problems ?

[c_hegge]

Re: Trust Asus P4 boards - no way

I'd be giving it a full re-cap. LTEC are junk, and so are Chemi-Con KZG (that's what the 16v caps look like). The problems you are describing don't sound like failed MOSFETS. usually, when they fail, the poard won't even POST.

[Quasar]

Re: Trust Asus P4 boards - no way

Mine's been in use for 5 years, overclocked (2.8 running @ 3.1), and nary a hitch. They were made right at the beginning to the middle of the bad cap era. Maybe -they- cut costs, but more likely, costs were cut on -them-, unknowingly. The blame can be spread around, but in the end, I think they (Asus) and the industry were snookered. Someone on here said that the majority of the issues with XP at the beginning, were more likely due to the bad caps, than flaws in the OS.

They still bring a pretty penny on eBay.

I have a P5AD2, and the vcore is all FL's, the vrm is Ruby MBZ's The bad caps are all Ltec LMB's, but given the extreme heat generated by the CPU in these, I'm amazed at the longevity of 4 years of 24/7 operation. All caps dated in 2004.

Your board (and mine) are excellent candidates for poly-modding. There are a few threads in here for that. Someday, I'll do mine, just for the heck of it. Maybe I'll get to see it OC'd by 20%. lol

Q

[EDIT: Additionally, do remember that you are dealing with an 8 or 9 year old item. You've got to change the plugs and the oil once in a while... ]

[PCBONEZ]

Re: Trust Asus P4 boards - no way

Yeah, I can't tell if those are KZG or KZE.
If you have any KZG those should go next.
Then, next phase, change all questionable caps down to 470uF.
-
If no change by then you need to start looking for non-caps problems.
.

[brethin]

Re: Trust Asus P4 boards - no way

This P4C800-E Deluxe is built around Intel's Canterwood chipset, the best of its era, and presumably the most expensive

Does the P4C800-E Deluxe use capacitors of similar calibre for a top-of-the-line board ?

Errr no

1500uf 6.3v VRM caps are Elite - not what their name implies

All 1000uf 6.3v capacitors are Ltec, a regular contestant for bad caps (dis)honour awards

And not to be outdone in the race to the bottom, the small 100uf 16v non-vented capacitors are GSC, arguably the worst of the worst

This board has four problems:

1. All fan headers are dead - fans connected to any of them, don't work

2. On-board sound is detected, but produces nothing - it's not missing jumpers on the FP_AUDIO connector, been caught with that before

3. BIOS Hardware Monitor says zero for 12v

4. Drains a CMOS battery fairly quickly

Are any of these problems likely to be caused by bad capacitors ?

I'm loath to spend time and money replacing them, only to end up with something no better than before I started

My first guess is a short, esp if its draining the CMOS battery quickly.

Remove the plastic cpu heatsink retention bracket, if you havent already, and flip the board over and look at the back side where the retention bracket was. Look close as there were cases where the bracket would be directly over a solder location and would smash it out and cause a short.

[PCBONEZ]

Re: Trust Asus P4 boards - no way

My first guess is a short, esp if its draining the CMOS battery quickly.

Yes, I agree.
A shorted cap in +5vsb or +3.3v is also a likely suspect and it might be a small 4 or 5 mm cap.
[Or +3.3vsb which is not from PSU but some boards create it from +5vsb on the board itself.]
.

[pfrcom]

Re: Trust Asus P4 boards - no way

Thank you Brethin, for the inspiration

Removed the retention bracket and had a look - nothing obvious wrong, although nearby there was some copper showing, after cleaning off with isopropyl alcohol, what might have been burnt lacquer

Had a look at the same area on top of the board, to find a burnt trace, hiding between a capacitor and the AGP slot

[pfrcom]

Re: Trust Asus P4 boards - no way

After cleaning, bridged the trace with a tiny bit of wire from a flat ribbon cable

[pfrcom]

Re: Trust Asus P4 boards - no way

Then encapsulated the fragile repaired area with hot melt glue

[pfrcom]

Re: Trust Asus P4 boards - no way

Capacitor replaced with a Sanyo WG, and another view of the repaired area

[pfrcom]

Re: Trust Asus P4 boards - no way

Underneath the replaced capacitor (right in the middle of the flare from the flash), and the copper visible below that

[pfrcom]

Re: Trust Asus P4 boards - no way

Replacement Panasonic FJs in the VRM

BTW, the 16v 1200uf Chemicon capacitors are KZE

Then the acid test:

1. CPU_fan header works, as does CHA_fan header

2. On-board sound produces audio

3. BIOS Hardware Monitor says 12.20 for 12v

4. CMOS battery - fingers crossed, will fit a new one and hope for the best

[PCBONEZ]

Re: Trust Asus P4 boards - no way

Good work!
.

[pfrcom]

Re: Trust Asus P4 boards - no way

Here it is, shod in Sanyo WG 1000uf 6.3v, replacing the Ltec

A quick check of the Sanyos with my Dick Smith ESR meter showed .01 or .02 for all

Whereas the Ltec were from .12 to .15

Only problem after the replacements was, IT DIDN'T WORK

[pfrcom]

Re: Trust Asus P4 boards - no way

First impulse was throw it into the rubbish bin, but had spent too much time to give into that impulse

So persisted, and after painstaking examination found I'd made a solder bridge between a leg of a cap and one of the solder dots that are underneath the board

A bit of de-soldering with wick, cross fingers, try again and IT WORKS

The two are circled in this picture

What a relief - not intending to replace any more capacitors, the original Chemicon are KZE

Still had problems with draining CMOS battery, but while doing the Sanyos found corrosion between some of the pads for components which had not been fitted, in the vicinity of the battery holder

Cleaned these up, and hoping for the best - an overnight didn't result in significant battery discharge


Mods - could you please retitle this thread to "Asus P4C800-E Deluxe rejuvenation", maybe more suitable in retrospect

[PCBONEZ]

Re: Trust Asus P4 boards - no way

Conrats!

[PCBONEZ]

Re: Trust Asus P4 boards - no way

What uF, volts, can size were those LTEC LZP you removed?
Those were the ones with high ESR?
.

[kc8adu]

Re: Asus P4C800-E Deluxe rejuvenation

good save!
a lesson in this one is that if it worked before you messed with it its something you did.recheck your work till you find it.
now on to the poly mod.
btw one of our shop helpers has one of these in his recording studio pc and wont ever give it up.
it is also poly modded.
iirc i posted the recipe and was modding his board at the time.