Intel DQ45CB No Boot

[Per Hansson]

Re: Intel DQ45CB No Boot

If that is a CapXon then it is not LOW ESR but a general purpose (GP) capacitor.
https://cdn.badcaps-static.com/pdfs/...c0932e41ea.pdf

[Russ17]

Re: Intel DQ45CB No Boot

Thanks for the capacitor info. I will source a low ESR type.

Do you think that this could make enough of a difference, to fix the non booting?

Is it likely, that other capacitors are also bad, even if not bulging? Can they be tested reliably in-circuit with any test equipment?

Would a bad capacitors exhibit high ripple voltage on the VCore or other voltage rails, which would then affect data signals due to supply voltage fluctuations or generally affecting microprocessor operation?

I appreciate you taking the time to reply.

[ChaosLegionnaire]

Re: Intel DQ45CB No Boot

looks like a boardful of red brown kzgs and lime green ltecs, both known bad caps brands and series. not sure about the date codes on the kzgs tho. kzgs after a certain date code are okay. not sure if per hansson can see the date codes on those kzgs. he is very good with them. looks like a major recap may be in order.

[Per Hansson]

Re: Intel DQ45CB No Boot

Agreed on the Ltec's, they are known to be quite terrible and fail with no signs.
As for the KZG's I can't see any date codes, but the board looks like it was manufactured sometime in 2009.
But it brings up an interesting question: what was the capacitor that failed?
If you still have it can you post clear pictures of both sides print on it?
As for the probability that the Capxon replacement is not good enough, that always comes down to a guess.
If you don't want to place an order maybe you have some other board where you could scavenge a really LOW ESR capacitor or solid polymer capacitor for a test?
As for testing caps in circuit: no, generally that can't be done because there will always be another capacitor somewhere in parallel that you are measuring too.

[Russ17]

Re: Intel DQ45CB No Boot

Hi

Thanks for all that are trying to help me out.

I have uploaded a picture of the faulty capacitor.

Russ

[Per Hansson]

Re: Intel DQ45CB No Boot

Ok, yea then I would not really worry about the Chemi-Con KZG caps.
I would more worry about the rest of the Rubycon MBZ caps and also the Ltec caps.
First par for the course would be to replace that cap you put in with what I mentioned in my previous post.
And get a Port80H test device so you know where the board gets stuck.
But as dicky96 mentioned the most obvious thing is to check the RAM and CPU.

[Russ17]

Re: Intel DQ45CB No Boot

I did test the RAM in another system and it is OK, but still the faulty MB sometimes gives three beeps (Memory issue according to Intel website) when in the faulty MB.

Either way, the faulty MB is not behaving in the same way that the good one does.
Good one will power up itself, when PSU is first powered up, then will shutdown again on its own after about 10 seconds, before the system boots the OS. Pressing the power switch will start it up in the normal way.

Bad one powers up itself upon PSU switch on, but does not power down on its own. I can force it off by holding the power switch for 4 seconds.
Pressing the power button will start boot up, but the MB shuts down after 2 seconds, then waits 5 seconds, then powers up again on its own, but does not boot to OS, wake the screen or power the mouse LED, but sometimes three beeps are heard, but not every time.

[Per Hansson]

Re: Intel DQ45CB No Boot

The board is only £20 on eBay from UK sellers so that seems a quite logical way to go.

[Russ17]

Re: Intel DQ45CB No Boot

Thanks for Ebay idea Per.

As the whole PC was given to me, I was trying to see if a budget repair was possible.

Looking at the cost of sourcing MBZ series capacitors, plus the chance of success (in my case <50% due to a poor soldering iron), it doesn't seem sensible to try to repair this MB.

I was just hoping that I could find one bad capacitor and that would be good enough to spark it into life.

I think it is time to close the casebook on this one.

I have learned a lot, even though a repair has been possible.

Sometimes, the most effective repair is not to attempt a repair, and channel the funds into something with a better chance of success.

Thank you to all who have taken their time to help me out.

[dicky96]

Re: Intel DQ45CB No Boot

Well you certainly have the correct attitude though Russ

I often fix (or attempt to fix) stuff that isn't worth fixing. That's how I learned to fix stuff more of the stuff that is worth fixing. And hey-ho I'm still learning. And that almost certainly goes for all the others here

You have recognized the one thing you gained from all this - the fact that you have learned a LOT. And I suspect it was fun too.

Maybe you will also come to the decision it is a skill worth the time to learn, and come back sometime..... With a better soldering iron

Oh PS: You are correct, CPUs are pretty robust, and well shielded from the 'outside world' once on the motherboard - but I've seen quite a few fail and invariably it is because the old heat sink compound dried up so they overheated.

[Russ17]

Re: Intel DQ45CB No Boot

Hi Rich,

I too have spent a lot of time trying to fix the un-fixable - my wife will tell you the same.

I don't like admitting defeat on anything, but as it happens, I have literally just been gifted another working PC, with an i3 Processor and 8Gb RAM, so spending any amount of time on the broken one, would not be wise at this time. The MB wont go in the bin just yet though.

I have an old PC PSU, which has some 10V 1000uF capacitors on it (pictures attached).

Does anyone think that it would be OK to use these to replace the Rubycon MBZ capacitors (5 in total required I think), just to see if I can save it one last time?

I think I will invest in a T-15 soldering unit as you suggested as the station I have seems to be a bit rubbish, although I did manage to remove and replace a 10V 2200uF capacitor to fix my ageing DVD/VCR!

Thanks again for your patience ans ongoing support.

I have a Gigabyte gaming Motherboard GA-P67A-UD4-B3 which doesn't work, but I think that one or more CPU pins are damaged and one is missing, so that is definitely out of the question for repair by me - I watched some you tube videos of replacing the CPU socket, and high end equipment is required.

[dicky96]

Re: Intel DQ45CB No Boot

A T12 soldering iron is the one :-) Honestly, just buy one and it will be like a revealation!!

Admitting defeat is a good skill to learn.

Start a new thread for your Gigabyte mobo and show us your damaged socket - then we can see. many processor pins are just ground or Vcore and not even necessary so you could be lucky. Bent / damaged pins are often not too difficult to fix, because even I managed to do it successfully lol

Now I believe changing CPU sockets is an art - and I have not learnt it yet - I can remove them no problem without damage to the board but never managed to get the replacement to solder properly. I've seen it done with basic / home made kit but I can't even do it with a €3000 semi-automatic three zone mid range BGA rework station That will be the topic of a new thread for me soon because I am determined to do this so watch this space. There is a guy on here name 'diif', and probably others, who manage to do this with much cheaper kit than I have.

Good news for your gigabyte motherboard - here is the schematic, which gives us a fighting chance. If this is the wrong revision I have a few more versions.

I'm not a capacitor expert as you probably figured. I mean I can find faulty ones and change them but I have to rely on the clever guys here as to which sort I should fit. So for sure someone will come along and answer that question.

[ChaosLegionnaire]

Re: Intel DQ45CB No Boot

I have an old PC PSU, which has some 10V 1000uF capacitors on it (pictures attached).

Does anyone think that it would be OK to use these to replace the Rubycon MBZ capacitors (5 in total required I think), just to see if I can save it one last time?

nope... psu caps are not suitable to replace caps on motherboards. motherboards require ultra low or very low esr type capacitors. psu caps are of the normal low esr variety and typically dont work unless its for very low power filtering purposes like for the ps/2 or usb ports. and those caps on the psu are also of the dodgy and unknown brand type.

[Russ17]

Re: Intel DQ45CB No Boot

nope... psu caps are not suitable to replace caps on motherboards. motherboards require ultra low or very low esr type capacitors. psu caps are of the normal low esr variety and typically dont work unless its for very low power filtering purposes like for the ps/2 or usb ports. and those caps on the psu are also of the dodgy and unknown brand type.

I suspected they were very cheap Capacitors, but figured it was worth asking, maybe even worth taking a chance, but it seems that would equally be a waste of valuable time with little chance of success.

As always, I appreciate every response.

[Per Hansson]

Re: Intel DQ45CB No Boot

I have an old PC PSU, which has some 10V 1000uF capacitors on it (pictures attached).

Does anyone think that it would be OK to use these to replace the Rubycon MBZ capacitors (5 in total required I think), just to see if I can save it one last time?

It is unlikely to help, the capacitor is made by YC (Yang Chun) series LE but I can't find a datasheet.
That said it is likely to be lower ESR than the GP Capxon you have there now, or the same, so at least it would not be a downgrade.
I give it about a 3% chance of success

[Russ17]

Re: Intel DQ45CB No Boot

@Rich - new thread about the Gigabyte MB https://www.badcaps.net/forum/showth...64#post1024564

[eccerr0r]

Re: Intel DQ45CB No Boot

Would be interesting to have a POST card in these no-boot motherboards to see at least if it's doing something or not. But if it's not beeping with no RAM in it, that's not a good sign...

I have one of these boards as well, though will need to check again if it does that power up when coldplugged (may have something to do with turn on after power loss setting in BIOS?) like another intel board (P4/S478) I have which seems to have the same behavior as your "working" board. Not sure what the reason for this slight blip when restoring power.

[dicky96]

Re: Intel DQ45CB No Boot

eccerr0r
It seems the OP was already convinced by some random info on the internet that POST cards are useless

[eccerr0r]

Re: Intel DQ45CB No Boot

Oh well, his loss. It might not show accurate information but it does show signs of life that may otherwise not be detectable.

[Russ17]

Re: Intel DQ45CB No Boot

At the moment, this board has taken a backseat to other more pressing needs.

I will try a POST tester when I get one, as it would be interesting to see what is happening, even if I cannot decode the POST failure.

So, for now, this project is on hold.