single bad cap near northbridge causes boot issues?

[logic7]

Back again, this time with a different board. I haven't recapped the Asus P4G800-V I posted about last time (I'll get to it soon!) having bought a replacement to hold me over.

This time, I have a single bad cap on it's replacement: an ASRock P4VM890 board.



I've circled the cap in this stock pic since I forgot the SD card the pic I took was on. Anywho, this is the ONLY bad cap on the board. I've been having problems with this thing refusing to boot. I originally had a 3.4GHz P4 HT Prescott on the board along with a firewire card and Geforce 8400 PCI-E video card. It started to flake out on me, so I thought that maybe the PSU wasn't up to snuff and added an Antec 430W unit. Still flakey, I swapped the prescott core processor with a 3GHz P4 HT Northwood core unit, which solved the problem momentarily as the next day it was refusing to boot again. I removed the FW card and all was well until the next day. Removed the video card and reverted to the onboard video and it was ok again... unless I ran anything 3D related. I pulled the machine out yesterday and inspected the board and found this lone bulging cap near the VIA P4M890 northbridge.

Could this be the source of the problems I'm having? I'm completely puzzled by this since I have an old Gateway PC with an intel P4/i845 motherboard in it with bad caps everywhere (including those near the northbridge and PCI slots), yet it functions just fine.

[Pentium4]

Re: single bad cap near northbridge causes boot issues?

Absolutely it can cause it to not boot. The ESR is probably very high across that cap, and motherboards are only happy with ultra low ESR, so I'm willing to bet that's why. The Northbridge is used to for communication between the CPU and the RAM, so it's very important to be functioning properly

The one functioning just fine may be getting very low ripple from the PSU so sometimes you can get away with bad caps on the mobo if that is the case

[logic7]

Re: single bad cap near northbridge causes boot issues?

Absolutely it can cause it to not boot. The ESR is probably very high across that cap, and motherboards are only happy with ultra low ESR, so I'm willing to bet that's why. The Northbridge is used to for communication between the CPU and the RAM, so it's very important to be functioning properly

The one functioning just fine may be getting very low ripple from the PSU so sometimes you can get away with bad caps on the mobo if that is the case

Awesome! Since I forgot to bring the pic with me, I don't have the particulars of the cap so I can't swing by Frys to see if they have a replacement. Hopefully I'll have this issue solved by tomorrow evening! I'm TIRED of using the far slower gateway.

[Pentium4]

Re: single bad cap near northbridge causes boot issues?

Yeah I don't blame you! Although, I do not recommend getting caps at Fry's, from what I've seen they have a horrible selection and no low ESR caps. You would want to order them from Mouser or Digi-Key. So list the specs and we can find a good replacement for you. Hard to tell but those black caps look like OST or G-Luxon. Ideally, you would want to replace all of those, or at least the ones that are 1000uF or higher

[logic7]

Re: single bad cap near northbridge causes boot issues?

They're black with orange/copper markings. I'll post it up tonight when I get home.

[PeteS in CA]

Re: single bad cap near northbridge causes boot issues?

What P4 said. Get all the known junk out, and use good parts, even if it takes longer.

[logic7]

Re: single bad cap near northbridge causes boot issues?

Ok, finally got a chance to look at the cap: It's blue with copper colored markings. Evercon 1000uf 6.3V caps. There's quite a few of them on this board too.

[LLLlllou]

Re: single bad cap near northbridge causes boot issues?

Ok, finally got a chance to look at the cap: It's blue with copper colored markings. Evercon 1000uf 6.3V caps. There's quite a few of them on this board too.

To call Evercon shit would be an insult to actual shit.

[Pentium4]

Re: single bad cap near northbridge causes boot issues?

Yes....Replace 100% of the Evercon if you plan on using the board. They are some of the worst of the worst. Even in the low stress roles they will dry out and die eventually

[y_not]

Re: single bad cap near northbridge causes boot issues?

To call Evercon **** would be an insult to actual ****.

That's pretty durn funny! Thanks for the laugh.

[logic7]

Re: single bad cap near northbridge causes boot issues?

Yes....Replace 100% of the Evercon if you plan on using the board. They are some of the worst of the worst. Even in the low stress roles they will dry out and die eventually

I counted them up. 18 Evercon 1000uf caps on the board. I'll start with the bad one now and eventually replace them all. Any recommendations on replacement caps?

[Pentium4]

Re: single bad cap near northbridge causes boot issues?

What is their voltage and dimensions? I'm guessing they are 6.3V? If so I would get these: http://www.digikey.com/scripts/dksea...=0&pageSize=50

[logic7]

Re: single bad cap near northbridge causes boot issues?

What is their voltage and dimensions? I'm guessing they are 6.3V? If so I would get these: http://www.digikey.com/scripts/dksea...=0&pageSize=50

Yeah, I posted the voltage last night.

That looks like the right size, I'll double check when I get home.

After this one, my Asus board is next, followed by the Gateway/Intel unit and my server's Tyan dual Athlon MP board which, like the Gateway, has plenty of leaking caps yet still runs like a champ (current uptime is about 2 months)

[Pentium4]

Re: single bad cap near northbridge causes boot issues?

Whoops, my fault Sounds good, make a separate thread for each of them

[logic7]

Re: single bad cap near northbridge causes boot issues?

found a local supplier for Nichicon caps. Lil pricey ($1.05 each... sheesh), but I'm going to replace the caps in groups 'cause I need to get this PC back up and running by tomorrow evening.

[Pentium4]

Re: single bad cap near northbridge causes boot issues?

What series are the nichicon caps?

[lexwalker]

Re: single bad cap near northbridge causes boot issues?

found a local supplier for Nichicon caps. Lil pricey ($1.05 each... sheesh), but I'm going to replace the caps in groups 'cause I need to get this PC back up and running by tomorrow evening.

Make sure they are low ESR or low impedance models such as HE, HM, HN, HZ, PM, PW or PS series. Also do beware of counterfeit/fake Nichicon capacitors. Quite easy to detect counterfeit/fake ones from the rubber seal/bung at the bottom, and sometimes a different vent gives them away (e.g. using "Y" vent instead of standard Nichicon "X" vent).

[Topcat]

Re: single bad cap near northbridge causes boot issues?

I have all this stuff you know.... https://www.badcaps.net/store/

Try supporting the site a little...

[logic7]

Re: single bad cap near northbridge causes boot issues?

I have all this stuff you know.... https://www.badcaps.net/store/

Try supporting the site a little...

No doubt. I did pick up the caps from the local guy 'cause I needed that machine up and running ASAP for a project (plus I do like to support local businesses, even if their prices are a bit crappy)

I still need to get 1800uf 6.3V caps for my other P4 board. I'll order them from you this time.

[theokretes]

Re: single bad cap near northbridge causes boot issues?

Also, those two evercons at the top left (above the brown slot right next to the realtek chip), those are the decoupling capacitors. If you replace both with 470uF ones the onboard audio will actually be able to get bass response.
Make sure they're not low-ESR though. Some decent general purpose ones will work fine (Nichicon, Rubycon or ELNA will do just fine).

I'm assuming they underrated them at 100uF (or worse, 47uF).