golden rule... check power supplies...
a) get schematics for the mobo
2) check all power rails on the board
iii) check clock signals...
ok, how do you check the rails/clock signals then? You mean the phases right? just with a multimeter or do you need a logic analyzer?
Btw yes as I said I tried multiple know working components already, cpu et all. I have 5 x58 systems and tons of older ones that I've repaired in various states already, like broken pins, bad caps ect, but this power issue is a new learning thing for me, so trying to see what I can do. I'm fixing socket pins/reballing/replacing obviously fried smds and all sorts of board level stuff, but trying to learn board level diagnostics a lot better, and get a better idea of the architecture beyond just replacing obviously physically damaged stuff.
Yes, I've taken one of the cpu caps out to analyze it as well, they are tough, but doable. It was also physically damaged, it looks like from someone trying to put too big of a cooler on it or something, it also showed a similar overcapacitance, so I guess they're probably ok. Thanks for the help in that.
There are usually caps by the atx power supply connector that I've found bad caps there before that were completely bad in other boards that definitely stopped the system from booting. I agree though probably caps near the socket, the system might still power because it would still be getting power to the chips/architecture that boots the system right?
From videos I've watched there seems to be a main controller chip that checks voltage and connections that when you press the power button it decides if it wants to try to run the power supply but that was an older board, so maybe that is all in the cpu now I guess? I need to find schematics for this board. It's an xfx 58i..any idea where I would find those? A quick google search yielded nothing. Maybe there are general x58 chipset schematics somewhere that would prove useful?
Found a really good vid... so this is for a 2011 board, but I guess the main chip I'm looking to measure is the pwm.
I wonder if I solder wire onto the caps from the last point before they go to the cpu and then measure from ground if I can monitor voltages going to the cpu like that one vid that Dave Jones had with like 8 multimeters going to monitor all the different phases. That would be cool. lol
The pwm on this board is an it8268r. so maybe I can figure it out if I look up the pinouts on it.
http://images.people.overclockers.ru/195575.gifhttps://translate.google.com/translate?hl=en&sl=ru&u=http://www.rom.by/forum/Mat_GIGABYTE_GA-EP35-DS4_zapuskaetsja_no_net_pitanija_na&prev=searchIt's so weird that all the board level repair stuff is either in Russian, hindi, or chinese. Wth everyone in the western world just throws their boards out I guess.
Only one pin on the pwm seems to have power...sooo now where do I go? lol Also which pins tell it to power on..hmm.
Anyone know of a video/explination like this in english and newer? lol
Turned it on using this trick.
Still no post though. Nothing blew up or burned out after replacing all the caps, so I count myself lucky for that at least. If something had blown up though I might have known what to replace. lol
oh the pwm is the isl6336, not the other one...researching that now.
ok well at least I can see some circuits now.
http://www.datasheetdir.com/ISL6336+PWM-Controllers