Mobo not booting - board or cpu ?

[eyepea]

Computer not booting.

Tried various things. Still no luck.
ithin okkoma galawwa.

Now only mother board with cpu and cpu fan.
board is intel DG31PR
Board out of case to eliminate shorting to case issues.
Vacuumed to avoid any dust issues or any mobo shorts. (Of course can't be 100% sure)
Can't see any damage on mobo. Anyway me no x-pert
cpu removed and re-seated.
Connected only psu main connector and 12v connector.
(psu is a known good working one).

(1)
Switched on psu.
mobo light on.


(2)
shorted power switch contacts.
cpu fan starts.
no beeps!

since no ram, if mobo booted, there should be ram error beep - am I right ?
here am assuming on-board beeper working. Anyway to test that ?

(3)
shorted power switch contacts for 10 sec.
cpu fan stops.

-----

Does this behavior pattern indicate what the problem is ?

since still prob,

reset the cmos - removed cmos battery, left for 24 hours. also shorted battery contacts as advised in a previous thread. put back battery.

retried steps (1),(2) & (3). No beeps.

Borrowed known good working post card.
Fixed on pci slot 1

(1)
Switched on psu.
mobo light on.
post card 3.3v led on. (same behavior on a working similar mobo)

(2)
shorted power switch contacts.
cpu fan starts.
post card 5V, 12v leds in addition to 3.3v one on (same behavior on a working similar mobo)
BUT post card does not start counting!
no beeps either.

(3)
shorted power switch contacts for 10 sec.
cpu fan stops.
post card back to 3.3v led only.

----

since pci slot may have contact prob, tried post card on pci slot 2, and repeated steps (1), (2) and (3). No luck.
(Well have heard that post card should be in pci slot 1 usually. But have seen post card ok in either pci slot in working mobo )

----

I don't have another compatible cpu or mobo at the moment to swap and test.
(well swapping cpu is not my favorite thingy, and don't wanna mess other peoples working computers either )

Anything else I could try ?

How can I know if mobo bad or cpu bad ?

since post codes not shown, either post is not started, or did not come up to a stage where post codes are outputted.

When mobo powered on, gpu chip and io controller chip etc get warm.
under area of cpu gets warm.
But I could not detect cpu heatsink warm as fan is running and I did not keep board powered on for long time.

Can the cpu fry, if powered on without cpu heatsink ?
If cpu will detect cpu fan on, I can have the fan just connected.
In such a situation should the cpu shutdown immediately and be protected ? Should get high temp alarm beep ?
Just wondering to check if cpu gets warm

cpu cold mean cpu dead or it can mean good cpu but mobo fault ?
cpu warm mean working cpu or even bad cpu can get warm ?

Any idea please ?

Did not try this as I don't want to damage the cpu in case it is working
Remember reading somewhere that intel cpus are difficult to kill under normal conditions and protection circuits would shut it down.
True or falls I don't wanna find out the hard way

Well getting back to my question,
in the problem am having, how to find out if cpu bad or mobo bad ?

Any help, ithaaamathma isthoothi

 

[boyzsasith]

try to boot by adding a new PSU,

 

[ruwanjrc]

processor burul welaaa.. pros eka galawala set karala balapan

 

[eyepea]

thanks.

Actually tried two psu. No luck

Both psu can boot another machine with similar but slightly later faster cpu+mobo, meaning other machine may take more power than problem machine. (unfortunately can't use that cpu + mob for swapping)

So here am assuming both the psu can supply enough power to the problem mobo + cpu to boot.

anyway will try a new psu if I can get hold of one.

 

[eyepea]

processor burul welaaa.. pros eka galawala set karala balapan

thanks.

I did re-seat the cpu (remove, and fix back with thermal paste). Will try that again and see.

 

[maduranga_it]

problem in your processor machan
heat zn eka hariyata connect da balanna
processor sockets pins clean karala balana

natnam sorry thama

 

[ruwanjrc]

harida machooooo

 

[eyepea]

problem in your processor machan
heat zn eka hariyata connect da balanna
processor sockets pins clean karala balana

natnam sorry thama

thanks.

tried re-seating cpu as ruwanjrc suggested. So heat-sink was re-installed.
hopefully it is ok

I have cleaned ram contacts with an eraser and can try same on the cpu as this is a socket 775 cpu.

But never tried cleaning the socket pins before.

A quick google shows me the way to go about it is a soft toothbrush and isopropyl alcohol.


Is this the way to go about it ?
Any ideas are welcome please

Will try that and see

 

[eyepea]

harida machooooo

thanks ruwanjrc
appreciate your checking.

took some time as I had to clean out the previous thermal paste before applying again, after re-installing the cpu

but no luck

will try cleaning the socket and cpu contacts as maduranga_it had suggested.

must see

 

[maduranga_it]

thanks.

tried re-seating cpu as ruwanjrc suggested. So heat-sink was re-installed.
hopefully it is ok

I have cleaned ram contacts with an eraser and can try same on the cpu as this is a socket 775 cpu.

But never tried cleaning the socket pins before.

A quick google shows me the way to go about it is a soft toothbrush and isopropyl alcohol.


Is this the way to go about it ?
Any ideas are welcome please

Will try that and see

yeah use soft brush no need 2 use liquid
its not advisable to use eraser to clean possessor pins if available use soft cloth (LCD cleaning tissue)

 

[eyepea]

yeah use soft brush no need 2 use liquid
its not advisable to use eraser to clean possessor pins if available use soft cloth (LCD cleaning tissue)

aha! ok thanks!.
I will try that and see.

(now have to grab some lunch first, and have a steady hand )

thanks very much for the help from all of you.
Will get back...

 

[eyepea]

thanks all for all the help

After cleaning and trying (tried twice) still same prob
Not sure if my cleaning was ok though

Well waiting to find a mobo or cpu to try a swap
Must see.

 

[boyzsasith]

Hmm yeah!!

thanks.

Actually tried two psu. No luck

Both psu can boot another machine with similar but slightly later faster cpu+mobo, meaning other machine may take more power than problem machine. (unfortunately can't use that cpu + mob for swapping)

So here am assuming both the psu can supply enough power to the problem mobo + cpu to boot.

anyway will try a new psu if I can get hold of one.

Hmmm

 

[MeGusta]

I replaced almost 3 Intel DG33's...piece of shit with cheap ass capacitors never a intel again.brought a Cheap asus one after that.No errors since then.Sry bro but try your cpu with some freinds mobo that's the only way,or other way around

 

[Hayao]

bumpi

 

[eyepea]

I replaced almost 3 Intel DG33's...piece of shit with cheap ass capacitors never a intel again.brought a Cheap asus one after that.No errors since then.Sry bro but try your cpu with some freinds mobo that's the only way,or other way around

thanks. waiting to catch some mobo for a swap
It is not fun to remove and replace a 775 board h/s fan assembly and cpu.
So can't use a comp that is required for day to day work

Intel Oh well I guess quality must be very low now!
These days 775 socket boards are not that common. Everyone is trying to sell i*
For 775 boards, some places have only stuff like foxconn, biostar, asrock and some more unheard of brands.

Anyone any comments on these boards pls ?

 

[jds2012]

Bump

 

[Bender]

if ur talking about a no display error. after reading all ur checking steps i say ur mother board is the faulty part. replace it or send it for warranty. u can't buy the brand of ur choice because recently DDR2 775 boards are rare to find. only used ones available in lot of shops. but before you buy a board take ur parts to a computer shop and let them check the fault first. good luck.

 

[eyepea]

found another working 775 mobo.

fixed the cpu in prob mobo to this working mobo and it is working - so cpu good
but tried other cpu on problem mobo - not working.

Well I tried something else too.
Powered up both mobo without cpu in socket. cpu fan just connected to mobo.
I observed the same scenarios with the same steps on both good mobo and bad mobo.

Hmmmm so more or less in bad mobo, when a working cpu is present even, it is as if no cpu!

Yeah this can be due to bad contacts in cpu socket and also I was not successful in cleaning properly.

Anyway to differentiate between bad cleaning and bad mobo ?
( Well may be nothing much can be done but good to know )

Can take to a repair shop, but now no warranty so shop guy would be more interested in selling a new mobo


thanks.

 

[rikazahamed]

same prob here