Not sure about the sequence of events after you press the ON button. I have a Gigabyte GA-81HXP MoBo with a 2.8 P4, 512Gb RAMBUS. It suddenly decided not to boot. You press the button the fans start up, the power supply light comes on - and then everything goes off. As far as I can discover, as the supplies come up a 'power good' signal is sent from a chip on the MB to the PSU to maintain the supplies. All the supplies seem to coming up (checked with multimeter)but I'm not sure if the 'power good signal' is a pulse or a permanent voltage and if I can measure it or not. Common sense tells me that the PSU is overloaded so I changed the PSU for a 500 watt PSU with the same result. This meant there was a possible power line short to deck so I changed the MB! Same result! What do I do now? Any help would be greatly appreciated.
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Need a power supply expert 3
- Thread starter nob1
- Start date
pcdoc4christ
IS-IT--Management
Arthur:
Sometimes a hardware device will fry a motherboard. Not sure if you swapped anything out to try on the other motherboard. If you do suspect a hardware device damaged both mobos, don't try it on the new one you purchase!
Also, a power surge may damage a system board. Not sure if this is a problem in the UK. If it is in your area, consider purchasing high-end surge protectors to protect your PCs.
Regards,
Doc
======================================
"Freely you have received, freely give." --Jesus
pcdoc4christ@yahoo.com
Sometimes a hardware device will fry a motherboard. Not sure if you swapped anything out to try on the other motherboard. If you do suspect a hardware device damaged both mobos, don't try it on the new one you purchase!
Also, a power surge may damage a system board. Not sure if this is a problem in the UK. If it is in your area, consider purchasing high-end surge protectors to protect your PCs.
Regards,
Doc
======================================
"Freely you have received, freely give." --Jesus
pcdoc4christ@yahoo.com
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1
- #22
About the mobo, it was discontinued only because of the rambus ram.
Lots of mfgrs only made one board with rambus and stopped as there were court issues to be dealt with. Actually they are still going on in the courts although just lately some or all of it has just now been settled. Rambus was set to be the future but ddr took over instead because there were no fees for using the technology whereas rambus wanted fees for every stick of ram sold.
Rambus could come back even yet, but prolly not.
Good advice + great people = tek-tips
Lots of mfgrs only made one board with rambus and stopped as there were court issues to be dealt with. Actually they are still going on in the courts although just lately some or all of it has just now been settled. Rambus was set to be the future but ddr took over instead because there were no fees for using the technology whereas rambus wanted fees for every stick of ram sold.
Rambus could come back even yet, but prolly not.
Good advice + great people = tek-tips
- Thread starter
- #23
You're welcome on the rambus, I have followed it a bit as I have an intel vc820 with rambus that i really like, its fast.
Darn, thats pretty scary if the cpu was the only common item.
I dont know if there is any way to test a cpu not plugged into a mobo, but that sounds like the kind of thing you need right about now.
Maybe someone out there will know the answer to that one, i dont.
Then again, it could be the cpu is only shutting down to protect itself. Hard to say.
Good advice + great people = tek-tips
Darn, thats pretty scary if the cpu was the only common item.
I dont know if there is any way to test a cpu not plugged into a mobo, but that sounds like the kind of thing you need right about now.
Maybe someone out there will know the answer to that one, i dont.
Then again, it could be the cpu is only shutting down to protect itself. Hard to say.
Good advice + great people = tek-tips
How about testing your power supply. I know you have a new one but i just dont know what else to tell you.
Its a good tutorial for anyone.
Good advice + great people = tek-tips
Its a good tutorial for anyone.
Good advice + great people = tek-tips
nob1, quote!
I'm back. I've done everything Paparazi suggested
If you have, then how come "the power ON lamp flickers briefly"
I assume you mean the power light on the case? my point is disconnect everything including front panel lights and switches, IDE cables, molex connectors, no addon cards, nothing.
The most common things to cause shut downs on initial post.
Shorted out Hard drive
Failing power supply
Shorted out CDrom device
Addon card of some description
Loose wires in the power cord, loose terminal connections to the PSU pins
Brass mounting standoff post in wrong position shorting motherboard.
CPU fan connected to the wrong fan header or bad rpm signal from the fan itself
Trapped shorting wire
Bent floppy drive pins, shorting
Badly flexing mainboard mounting back plate touching underside of motherboard
Incorrect IDE cable orientation
Sticking reset or power button
A failed CPU usually allows the fans to continue to spin but without post
Failing motherboard
Bulging caps (carefully check capacitors on the motherboard for signes of bulging or leaking, see this:
It's just got to be one of these!!!
Martin
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Participate and help others.
I'm back. I've done everything Paparazi suggested
If you have, then how come "the power ON lamp flickers briefly"
I assume you mean the power light on the case? my point is disconnect everything including front panel lights and switches, IDE cables, molex connectors, no addon cards, nothing.
The most common things to cause shut downs on initial post.
Shorted out Hard drive
Failing power supply
Shorted out CDrom device
Addon card of some description
Loose wires in the power cord, loose terminal connections to the PSU pins
Brass mounting standoff post in wrong position shorting motherboard.
CPU fan connected to the wrong fan header or bad rpm signal from the fan itself
Trapped shorting wire
Bent floppy drive pins, shorting
Badly flexing mainboard mounting back plate touching underside of motherboard
Incorrect IDE cable orientation
Sticking reset or power button
A failed CPU usually allows the fans to continue to spin but without post
Failing motherboard
Bulging caps (carefully check capacitors on the motherboard for signes of bulging or leaking, see this:
It's just got to be one of these!!!
Martin
We like members to GIVE and not just TAKE.
Participate and help others.
- Thread starter
- #28
Once I encountered similar problem on my friends PC, but he's waited a bit longer to shut off.
Eventualy I found out that he missmounted CPU Cooler (the Cu core part wasn't on CPU core 'cause he flipped cooler for 180 deg) so the CPU autoprotected himself on rapid temp grow. Maybe you also have a problem in CPU-Cooler "connection" ?
best wishes in solving this "worst case scenario" problem
Marko
Eventualy I found out that he missmounted CPU Cooler (the Cu core part wasn't on CPU core 'cause he flipped cooler for 180 deg) so the CPU autoprotected himself on rapid temp grow. Maybe you also have a problem in CPU-Cooler "connection" ?
best wishes in solving this "worst case scenario" problem
Marko
MCesic could be right here!
but the reason no-one else has pointed this out is because it appears the computer in question has been working fine at some point, therefore it wouldnt be improper installation of the cpu, would it.
Good advice + great people = tek-tips
but the reason no-one else has pointed this out is because it appears the computer in question has been working fine at some point, therefore it wouldnt be improper installation of the cpu, would it.
Good advice + great people = tek-tips
- Thread starter
- #31
I guess anything can be done, but its a lot harder to "missmount" a P4 than, say, an athlon xp. The athlon heatsink is not square on the bottom and so it has to be put on the right way or it doesnt sit properly and wont work.
Since we are on the subject, might as well state the obvious. You have to put a thin but obvious coating of thermal paste on the cpu. What i do is put the thermal past on the cpu, put the fan down on it and then lift it up. I can now see where the cpu meets the heatsink. So i spread a very small amount of thermal paste just in the area of the heatsink that now has some thermal paste on it, just to fill in the cracks that the eye cannot see. Then i smooth out the thermal past on the cpu and make sure there is still enough on there, if not, add a tiny bit more. A thin covering is all thats needed.
Then make sure the black plastic levers on top of heatsink are opposite each other and set the heatsink fan unit down on the cpu. Make sure the bracket is holding on all 4 sides and move the 2 levers to the other side and thats it.
Im sure you have done this, but just in case.
Good advice + great people = tek-tips
Since we are on the subject, might as well state the obvious. You have to put a thin but obvious coating of thermal paste on the cpu. What i do is put the thermal past on the cpu, put the fan down on it and then lift it up. I can now see where the cpu meets the heatsink. So i spread a very small amount of thermal paste just in the area of the heatsink that now has some thermal paste on it, just to fill in the cracks that the eye cannot see. Then i smooth out the thermal past on the cpu and make sure there is still enough on there, if not, add a tiny bit more. A thin covering is all thats needed.
Then make sure the black plastic levers on top of heatsink are opposite each other and set the heatsink fan unit down on the cpu. Make sure the bracket is holding on all 4 sides and move the 2 levers to the other side and thats it.
Im sure you have done this, but just in case.
Good advice + great people = tek-tips
You know you might save some time by spending US$35 and get a mainboard analyzer. Actually it is a boot analyzer, but the way they work is to track the POST codes generated by the mainboard and display them as they come. You plug it into a pci slot and power the board up. The device should come with a manual that lists the post codes in order (hexadecimal, of course). You simply go down the list until you find the code at which the analyzer stopped, and read the descriptions of the codes which did post; you should be able to glean what component is failing by doing this.
Now, that being said, I have had some really weird issues with Gigabyte boards. It came down to this: we suspected that the power supply had surged or otherwise glitched and consequently damaged the power control "logic gates" in the bios/MB circuits. This came to me after talking to a PCB technician who has seen such things before. It cause me so much heartache that I have sworn off Gigabyte boards.
Now, that being said, I have had some really weird issues with Gigabyte boards. It came down to this: we suspected that the power supply had surged or otherwise glitched and consequently damaged the power control "logic gates" in the bios/MB circuits. This came to me after talking to a PCB technician who has seen such things before. It cause me so much heartache that I have sworn off Gigabyte boards.
I think this is related enough to continue in this thread ...
Several months ago, I began having problems with the keyboard. All 3 LEDs come on, and I can receive no input from the keyboard. I power down - and all 3 LEDs remain on. They will remain on until I unplug the keyboard from the case. Wait a few seconds, plug it back in, power up CPU - sometimes all 3 LEDs would light right up and stick ON when it posted - giving me a keyboard failure message, sometimes it would boot fine. This sometimes would have to be done 5-10 times in order to get computer to successfully POST and boot up. Tried changing the keyboard, worked fine for a day and then repeated same problem.
Finally, in order to maintain usage - family was ordered to never shut computer down - ran it a month with no problems. Finally, keyboard 'died' again ... tried another one, no dice. After a day or two of unplugging keyboard trying to get it to POST, finally I could not even get to a BIOS screen .. talked to several techies, general consensus was that the mobo was bad. Just replaced it with a new gigabyte board, less than 24 hours in - same keyboard problems ... so far unplugging the keyboard, then replugging it in and turning CPU on allows it to boot, but have a feeling it will increase the number of cycles needed ... Don't know if this may be related, but my optical mouse is also lit up all the time - even when CPU is off ? Power supply problems ? I tested the power supply with no load on it, and the voltages seemed fine, but maybe something in the TTL circuit ?
Any clues or suggestions greatly appreciated !
Several months ago, I began having problems with the keyboard. All 3 LEDs come on, and I can receive no input from the keyboard. I power down - and all 3 LEDs remain on. They will remain on until I unplug the keyboard from the case. Wait a few seconds, plug it back in, power up CPU - sometimes all 3 LEDs would light right up and stick ON when it posted - giving me a keyboard failure message, sometimes it would boot fine. This sometimes would have to be done 5-10 times in order to get computer to successfully POST and boot up. Tried changing the keyboard, worked fine for a day and then repeated same problem.
Finally, in order to maintain usage - family was ordered to never shut computer down - ran it a month with no problems. Finally, keyboard 'died' again ... tried another one, no dice. After a day or two of unplugging keyboard trying to get it to POST, finally I could not even get to a BIOS screen .. talked to several techies, general consensus was that the mobo was bad. Just replaced it with a new gigabyte board, less than 24 hours in - same keyboard problems ... so far unplugging the keyboard, then replugging it in and turning CPU on allows it to boot, but have a feeling it will increase the number of cycles needed ... Don't know if this may be related, but my optical mouse is also lit up all the time - even when CPU is off ? Power supply problems ? I tested the power supply with no load on it, and the voltages seemed fine, but maybe something in the TTL circuit ?
Any clues or suggestions greatly appreciated !
This thread is getting so long that i wonder if you shouldnt list what parts are common to both setups. Seems to me you have had 2 power supplies and 2 mobos, right?
That being the case, then its safe to say that a possibility would be one of the parts you are using on both setups is no good. But what parts have been on both.
cpu?
ram?
keyboard?
Good advice + great people = tek-tips
That being the case, then its safe to say that a possibility would be one of the parts you are using on both setups is no good. But what parts have been on both.
cpu?
ram?
keyboard?
Good advice + great people = tek-tips
Unfortunately - all the parts are common so far except keyboard and mobo ... never thought anything other than keyboard, PS, and mobo might cause this ?
mobo FIC AN19c and GIGABYTE 7VT600-RZ
cpu ATHLON XP-2200+
ram ddr 2700 (2)256meg
ps powertech 300w ATX
keyb LOGITECH internet and DELL quietkey
mobo FIC AN19c and GIGABYTE 7VT600-RZ
cpu ATHLON XP-2200+
ram ddr 2700 (2)256meg
ps powertech 300w ATX
keyb LOGITECH internet and DELL quietkey
You have even tried 2 power supplies, right?
Have you ever simply re-set the bios? I'd cringe if that does it after all the posts! But if it helps, so be it.
Try re-set the cmos. Move the jumper nearest the battery from the 1-2 to 2-3, take the battery out, and unplug all sources of power, all sources, leave it that way for an hour then move jumper back to 1-2 and put all power back on and try it, but just bare with minimum that will boot!
Also, check manual for mobo, i have seen some mobos even tell you to boot with the jumper set at 2-3, others say it will damage the mobo, so read manuals. Generally you dont try to boot with jumper at 2-3, only at 1-2, but, again, some differ, been there done that, i think its ECS mobos but not sure.
Good advice + great people = tek-tips
Have you ever simply re-set the bios? I'd cringe if that does it after all the posts! But if it helps, so be it.
Try re-set the cmos. Move the jumper nearest the battery from the 1-2 to 2-3, take the battery out, and unplug all sources of power, all sources, leave it that way for an hour then move jumper back to 1-2 and put all power back on and try it, but just bare with minimum that will boot!
Also, check manual for mobo, i have seen some mobos even tell you to boot with the jumper set at 2-3, others say it will damage the mobo, so read manuals. Generally you dont try to boot with jumper at 2-3, only at 1-2, but, again, some differ, been there done that, i think its ECS mobos but not sure.
Good advice + great people = tek-tips
Rezzij
I thought i was talking to the other person, Nob1
Please go make your own thread. It hard enuf trying to fix one prob without another person and theirs. I understand why you posted but you dont understand, we have to skim thru all these posts and dont always see the names.
Always better to make your own, even if the prob is same, the hardware is always different and the fix is often different as well.
thanks
Good advice + great people = tek-tips
I thought i was talking to the other person, Nob1
Please go make your own thread. It hard enuf trying to fix one prob without another person and theirs. I understand why you posted but you dont understand, we have to skim thru all these posts and dont always see the names.
Always better to make your own, even if the prob is same, the hardware is always different and the fix is often different as well.
thanks
Good advice + great people = tek-tips
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