Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

[Newbie2]

Hello people,

I am wondering if I should recap an old ASUS MEB-VM motherboard. It has an old Intel Celeron 466MHz Mendocino Socket 370 processor.

The capacitors on it are all SANYO 1000uf 6.3V CG series (the CG series has been discontinued) capacitors. They are 8mmx11.5mm in size, so they are not large capacitors.

I got one question though. That motherboard is almost 10 years old, and I'm wondering if I should replace the SANYO capacitors currently on that motherboard. I have a lot of Nichicon 1000uf 6.3V HE series 8mx15mm capacitors. The Nichicon capacitors I have look better in the specification sheet than the SANYO capacitors (I used the similar SANYO ME-CA series capacitors as a close reference to what the CG series capacitors are).

I am expecting to keep this motherboard working for a few more years, and while the motherboard is still perfectly stable I would like to extend its life for a few years.

Given the age of the motherboard and its capacitors, should I even bother to recap this old motherboard?

[Newbie2]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

bump...

[Scenic]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

I've never done a recap on an old motherboard (under 1GHz).

even my first self-built PC is still going strong.. no cap issues at all..

i'd say: if the caps are from a known good brand (like your sanyos), just keep it going (unless you have stability problems)
if they are caps from a known bad cap brand, recap it with some cheaper caps (OST or something), as it wouldn't make sense to put Rubycon MCZ (for example) on an old Socket370 Board not capable of newish CPUs (PIII 600 and up) because the caps would be worth more than the board

my first self-built PC has a Chaintech 6ESA2 mainboard (Slot1, intel EX chipset) with unknown caps ("G-Cap" ?! probably G-Luxon?!) but its still going strong without any issues at all.

running a 433MHz Celeron (S370 ; Mendocino) on a Slotket adapter overclocked to 541MHz (83MHz FSB)
it's my Win98SE retro gaming system (with a GeForce 2 GTS (32MB DDR) and 2 Voodo II 12MB in SLI + a classic Soundblaster 16 ISA (non-PnP)

[PCBONEZ]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

I agree with Scenic.
There isn't a need to re-cap.

.

[Newbie2]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

I just replaced 8 capacitors on it with Nichicon HE series 1000uf 6.3V capacitors, and I still have 10 capacitors left to replace.

This motherboard is very easy to recap, unlike other motherboards where I have failed to recap, the caps on this motherboard just slip right out once I heat the solder joints with my soldering iron. I'm going to continue recapping this motherboard as practice with my 60W 375c soldering iron (its temperature depends on what tip is used on it).

[Newbie2]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

Yesterday I have replaced all 18 1000uf 6.3V capacitors on it. I used Nichicon 1000uf 6.3V HE series capacitors to replace the old SANYO capacitors.

The new Nichicon capacitors are slightly taller than the old SANYO capacitors, but their locations on the motherboard don't appear to interfere with any computer components.

Also, I tested a few of the old SANYO capacitors. They were all between 780uf to 800uf, which is at least 200uf below 1000uf, and that shows how degraded they've been after so many years of intense use. The new Nichicon capacitors are all 1000uf to 1001uf, because they are new.

I haven't had time to put the motherboard back into the case and see if it still works, I'll do that either today after I get off work or tomorrow!

[PCBONEZ]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

Caps are +/-20% for uF when new and uF goes down with age.
This is expected and compensated for when the board is designed and values chosen. A good designer would probably assume uF degrades by 50% over the usefull life and choose values based on that.
(Don't count on that from el-cheap brand or cheap models of boards though.)

- So the Sanyos you pulled were fine. (For uF anyway.)
They had a several more years left in them.

Knowing you have fresh caps is nice though.
And HE is better than CG so the board should run good.

.

[Newbie2]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

The SANYO capacitors were perfectly fine and the computer was still stable, but I just wanted to recap the motherboard so it could have new capacitors.

The Nichicon HE capacitors are doing great, I'm actually typing on the computer (my old gaming computer) with the ASUS MEB-VM motherboard right now!

Also, the higher ripple current specification means that the Nichicon HE capacitors should be able to better withstand the higher amount of ripple from the L&C power supply than the old SANYO capacitors.

And this motherboard is actually an OEM motherboard produced for HP, so the startup logo is the HP logo. ASUS motherboards are good, but I believe the stripped-down motherboards they produced for HP were not as high quality in terms of the VRM design and the other onboard components (the SANYO caps were good though).

[kc8adu]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

it would be interesting to see how far the esr is from spec on the sanyo's you pulled.

[PCBONEZ]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

I have an Asus MEW-AM (another OEM Asus for HP) that I used to use as a shop board.
[Checking drives and such.]
I got lucky on it. - 100% Rubycon as original.

[PCBONEZ]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

it would be interesting to see how far the esr is from spec on the sanyo's you pulled.

I was thinking the same thing.

[Newbie2]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

it would be interesting to see how far the esr is from spec on the sanyo's you pulled.

The SANYO capacitors that I pulled out of the motherboard were normal according to specification (following the SANYO ME-CA series specification, which is the modern version of the SANYO CG series capacitors), with an ESR measurement of 0.22.

The Nichicon HE series capacitors I put in had a lower ESR value of 0.13, which should be better for the motherboard along with the new condition of the Nichicon HE series capacitors I installed on my ASUS MEB-VM motherboard.

I used an old ancient BK Precision 875A LCR meter to do the capacitance and ESR measurements, and here is what it looks like:

[PCBONEZ]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

How did you get ESR with that?

[Newbie2]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

How did you get ESR with that?

I don't know, my father said that the "D" option on it meant ESR or impedance. My father owns it (I was just borrowing it from him) and that's what he told me about 2 years ago.

I'm also confused, your "low ESR" capacitors are called low impedance capacitors on the specification sheet, for example the Panasonic FC series capacitors specification sheet here (The Panasonic FC series I heard are low ESR capacitors):

Also, he said that his meter was of better quality and accuracy than the popular Bob Parker ESR meter kits.

[Newbie2]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

Also, this was my first motherboard recap. I have mentioned recapping an old unstable QDI Advance 3 motherboard, but my father mostly did that since I was new to soldering back then.

I believe my success of this recap was from the practice I did on a junk motherboard that came out of an old HP computer.

Also, I did the "bad" way of soldering a new cap in. I tried to clean the solder holes with the solder wick, but it didn't work and there was still some solder in the middle of the hole. I just added some solder into the hole on the bottom of the motherboard, and then pushed the new cap's leads through until it was installed. Not the best way to do it, but my 60W Weller W60P soldering iron is limited to 375c (its temperature is controlled by what tip it has) and my solder wick isn't that great.

[PCBONEZ]

Re: Recap ASUS MEB-VM Socket 370 Mendocino Celeron motherboard?

I asked because to measure ESR (or Impedance) the meter has to have a signal generator. The meter says LCR, the R being Resistance which is DC and to measure R there is no signal generator.
-
But I read the manual for that meter and it is an Impedance meter but it only uses a 1kHz frequency and the standard in modern tables (for low ESR caps) is based on 100kHz. Old charts and I think other kinds of caps used/use 1kHz.

~ The other part. ~
Here is how I understand it. (And I could be totally hosed).

Impedance is both ESR and Reactance.

If current(I) and voltage(V) are in phase then Reactance is zero and in that case Impedance = ESR.

Meters use a square wave vice a sine wave so I and V are in phase most of the time during the cycle.

Because of that the terms ESR and Impedance are used interchangeably in those charts.

Units are the same for either term: milli-ohms at 20C at 100kHz.

~
If this is AFU someone tell me. I need an upgrade in that case.

.