PC goes dead after mobo change (%!?!#) 1

[Sparent]

So i bought a new mobo for a Athlon XP 1.7GB processor I had. The new mobo is a MSI K7N2 Delta. Also bought a new Power Supply Unit (psu): an Antec SmartPower 350W.

Plugged everything back according to specs but when i fire up the PC it stays on for about 5-6 seconds before stoping suddenly, as if someone had turned off the back switch!

Any hints, advices, solutions would be apreciated.

Thank you

Simon

 

[smaxted]

Have you tried old fashioned trouble shooting...starting out with the very minimum of cards, reseating everything, making sure processor installed properly, make sure the FSB is set correctly, proper memory, memory contacts clean....?

Scotty Mac a.k.a smaxted

"Another day, another problem"

 

[Sparent]

Yes, did all that besides, the RAM is Kinston 512MB DDR and is brand new, in fact we got it with the mobo.

I guess i should remove the video card and try without but then i can't plug in my monitor, no VGA connector without the Video card (MSI FX5200)!

Any other ideas?! Thanks

Simon

 

[bcastner]

Neither Windows XP or Win2k will take this change gracefully.

Some thoughts about what to do now:
(For Win2k and XP)

http://www.windowsreinstall.com/install/other/motherboard/win2k.htm

 

[paparazi]

Spins for a few seconds then turn off??
Two obvious possibilities:
The heatsink is fitted 180degrees out and as a consequence is not sitting squarely on the CPU core, this causes rapid overheating (5-6seconds) and the built in thermal protection kicks in and shuts down the CPU, hopefully" before damage occurs.
Again on similar lines, the motherboard must sense an rpm signal on the CPU fan header pins, if it doesn't, it will again shut the system down. So a faulty fan or one that spins too slowly will cause a shut down.
A common fault is to connect the CPU fan to the wrong fan header, also some variable fan speed controls can have the same effect.
Don't forget the thermal paste, on the CPU core only, about as much as a grain or two of rice in quantity.
Martin

Replying helps further our knowledge, without comment leaves us wondering.

 

[paparazi]

I assume it's not getting as far as loading Windows? but if it is bcastner has a good point.
With major upgrades like this it is advisable to clean install Windows, this is because your hard drive was setup on your old hardware so drivers have changed.
Martin

Replying helps further our knowledge, without comment leaves us wondering.

 

[Sparent]

Yes, I agree the new instalol might conflicy with w2k and XP but in this case the pc shuts down so fast the POST has not even time to complete and nothing comes on screen! Baffling no?

I will try reseating the heatsink on the CPU but as far as i know, there's no chance of this thing overheating within the first few seconds. We are talking 5 seconds here and the longest the PC stayed on was approximatively 30 seconds but in general 5-6 sec is the norm.

I tried without the floppy (unplugged) which had given me an error at first, no change.

Without the video card, no change.

I read somewhere that the srews used to fix the mobo to the box should not be in metal to metal contact with the board. Putting paper washers to isolate the two blah, blah, blah...

Any comments?

Thanks

Simon

 

[Nowell]

quote:

as far as i know, there's no chance of this thing overheating within the first few seconds.

If the heatsink is not fitted properly then yes there is a high chance that the cpu will over heat in 5-6 secs. i have actually fitted a heatsink round the wrong way and trust me the CPU does overheat very quickly.

Have tried viweing the CPU temp in the bios?

 

[jdunderhill]

Hi I quickly read your threads and it reminds me of the problem I had with my grandads PC, try swapping out the keyboard and mouse just by borrowing them off a friend to test

My grandad had a dodgy mouse and was causing exactly the same sort of thing, the mouse itself had a short in the cable and it was causing absolute havoc with the PC

Some things that happened were:

- PC Wouldn't power on
- PC got into Windows and then just lost all power and dies

It took me ages to trouble shoot and finally found what it was

 

[Novexx]

Dont Know about Athlon, but I have had two 350Watt (new & from different, reputable manafacturers)PSUs give me serious problems with straightforward P4 computers.

They either dint work whatsoever, ran for a few seconds, or would power up & then be unable to spin the HDD - so no boot from that.

Good luck.

Hardware is easy, Software is not!

 

[jurgen36]

I would say the power supply is not able to deliver enough power on the 5 volt line. Had the same problem tried 3 new 350 watt supplies and got nowhere in a hurry. Could start up by connecting a 12 volt battery to the 12 volt line. System continued then normally after disconnecting the battery. Solution was to change the 350 watt supplies to a 550 watt supply. No more problems. Apparently my P4 HT EE 3.2 CPU takes about 75 amps of current on the 1.5 volt line. Rated at 122 watt dissapation at 1.5 volts. But I do not know if the same applies to your cpu. Best of luck Jurgen

 

[Po0O]

try 2 remove everything except processor, ram and vga card and put all this stuff on antistatic board ..open the power using screwdriver or any metal stuff.. if its work fine then try use the power switch it maybe the problem.. then put the board in the case and make sure there no short on it and try again

 

[paparazi]

The Antec surepower 350watt is a quality unit and easily upto the job of powering your fairly average needs (unless you are not telling us something? 8 hard drives etc lol) so no worries there.
Let me just make one thing clear, if a CPU heatsink is not fitted correctly to an XP processor then it will overheat in 5-6seconds, if for what ever reason you ever forget to fit the heatsink, then you will need a new processor in less than 8 seconds.
If the heatsink is fitted the wrong way round it only touches the CPU core along one edge, so rapidly overheats (5-6 seconds) but if you are lucky and this is the fault, the CPU may be still OK.
Martin

Replying helps further our knowledge, without comment leaves us wondering.

 

[Sparent]

I reassure you the heatsink is installed. I'll remove it and reseat it again just in case but it looked good from the begining.

I am highly doubtful the new 350W Antec has anything to do with this. I have only the MSI FX5200 graphics card, 1 HD , 1 CD-Rom and 1 CD burner, connected to it. A a floppy drive, of course but that is it. Anyways, I tried restarting the PC with all these things unplugged to the power supply and it wouldn't work either!!

The very first time i started the PC (after cahnging mobo) it stayed on for more than a minute, then it went down and it hasn't lasted more than 10-12 seconds since then. The average is 5-6 seconds per session.

Does that give you anymore clues?

I am grateful for the help, please keep it coming.

Simon

 

[franklin97355]

Try removing all from the case and running it on a nonconductive surface to rule out shorts. If it still won't work get it back to the seller as soon as possible and exchange it.

 

[Novexx]

OK, you seem certain that it isn't the processor, and you have tried the stripped down boot with no difference. Just to rule out the graphics card in connection with power problems, remove everything, including the graphics card and try to boot. When the PC (or what is left) boots and find no graphics card, it should give you an audible post error, and continue to run in its usless state (i think), until it is switched of.

You say that apart from the mobo & processor the PSU is the only thing that you have changed. If you are confident in the processor this only leaves two things - mobo & PSU.

As jurgen36 and I both seem to know through experience, PSUs can & will provide difficult to diagnose problems (especially if they are ruled out of the equation because they are Antec and/or 350Watt).

The system which gave me problems with an Antec 350W & QTechnology 380W (both split new)was as stated a bog basic P4 with a Geforce4 card and 1 CDROM drive. Your PC has an FX card and two CD drives??

PSUs are a bit like processors in the performance stakes, an advertised 350Watt, possibly gives on average 370Watt,
on a good example more, and on a bad example, possible less that the stated 350Watts? And shitty PSUs, just like anything else will get through the net.

On a last word, to keep the PSU running, there are two lines connected to the ATX main connector plug that are responsible for telling the PSU remain on (from memory, they are a black and a green line, next to each other at one end of the connector(cant remember the terminal Nos), a poor line or connection here could also be causing your problem.

A

http://WWW search

on "power supply forum" will give you more info on this.

I could be giving you a bum steer here, but it all sound pretty familiar & I through experience, I no longer class sub 380Watt supplies as consistently reliable on modern PCs.



Hardware is easy, Software is not!

 

[jurgen36]

Novoexx
Yes you are quite correct. We now fitt a minimum of 400 watt supplies to all our systems. Had to many problems, even on standard computers. I do believe that modern mobos have far more stringent supply standarts as the older versions. Also power supply problems are extremely hard to diagnose, you are quite correct with this remark. We have more then 400 Pc's on campus and my tech's complained bitterly as I instructed them to change all PS to 400 watt units. But no more boot up problems since. Regards

Jurgen

 

[paparazi]

sparent
A heatsink/fan unit fitted 180degrees out, looks completely normal and is just as easy to fit the wrong way around.
I had one so called system builder who came in the shop for months complaining about freezing and rebooting and even though I told him to double check the heatsink he refused to accept the possibility that this could be the cause because, as he put it, it looked and fitted right.
He eventually bought the PC into us and sure enought the heatsink was as expected the wrong way around.
Now you maybe right, I hope so, but please check properly, don't just take it for granted because it seems to look right.
Recess in the base of the heatsink needs to be positioned over the raised part of the CPU socket.
A small quantity of heatsink paste must be applied to the CPU core only.
Martin

Replying helps further our knowledge, without comment leaves us wondering.

 

[Sparent]

Yeah, the heatsink was 180 degrees out ok! Thanks all!

So now the computer runs but I have nothing sowing on the monitor when it is plugged into the graphic card!! Ah well...

Thank you all,

Simon

 

[mainegeek]

I would guess to say that you are now properly cooling a "fried" cpu.