these voltages are all OK.
but I have to think more about PU701.
now measure voltage on PL402, PL504, PL505, PL303, and PL604 after turning on.
I hope we find the culprit soon.
Checkout how the keyboard lights react to the beeping and how the speaker sounds, it sounds like it doesn't have much power. Alienware light under the screen doesn't light up ether. https://youtu.be/-gfgggpdlqc
these voltages are all OK.
but I have to think more about PU701.
now measure voltage on PL402, PL504, PL505, PL303, and PL604 after turning on.
I hope we find the culprit soon.
Well here we go... I had measured PL504 and PL604 in previous posts with 0V as well.
instead of PL503, measure voltage on pins 5-8 of PQ505.
yes, PU502 seems fluxy. anyway, please measure voltage on its pins 1 and 3 and 7 according to the attached picture.
all the measurements are after turning on.
The board is out of the casing as the components being tested are on the bottom of the board.
red light on power botton means nvidia vga (descrete vga) is working just fine. otherwise it will light up green or blue or other color; it depends of mainboard to mainboard.
check lvds connector on mainboard if its all ok.
when u first power on pc after beeing disconnected, ull get 5 beeps = bad cmos battery. just power offf and on again and the 5 beeps disappear. now if u get 7 bepps it means bad lcd or bad cable. try connecting an hdmi cable and that 7 beep shoud disappear..... if u get image on hdmi, then ill suppose bad lcd (u already changed lcd cable and i suppose lcd connector on mainboard is ok.
instead of PL503, measure voltage on pins 5-8 of PQ505.
yes, PU502 seems fluxy. anyway, please measure voltage on its pins 1 and 3 and 7 according to the attached picture.
all the measurements are after turning on.
After mesuring PU502, I found puting a little presure on PU502 when booting would somtimes give:
1 beep, then 7 beeps repeat
2 beeps, then 7 beeps repeat
3 beeps, then 7 beeps repeat
4 beeps, then 7 beeps repeat
5 beeps, then 7 beeps repeat
6 beeps, then 7 beeps repeat
on multiple different boot tests.
PQ505
5 - 18.96V
6 - 18.96V
7 - 18.96V
8 - 18.96V
PU502 - pin layout as per your picture
1 - 24.2mV
2 - 0.0mV
3 - 13.1mV when not beeping, 13.4mV when beeping
4 - 0.0mV
5 - 0.0mV
6 - 0.0mV
7 - 5.12V
8 - 0.0mV
9 - 0.0mV
10 - 4.90V
red light on power botton means nvidia vga (descrete vga) is working just fine. otherwise it will light up green or blue or other color; it depends of mainboard to mainboard.
check lvds connector on mainboard if its all ok.
when u first power on pc after beeing disconnected, ull get 5 beeps = bad cmos battery. just power offf and on again and the 5 beeps disappear. now if u get 7 bepps it means bad lcd or bad cable. try connecting an hdmi cable and that 7 beep shoud disappear..... if u get image on hdmi, then ill suppose bad lcd (u already changed lcd cable and i suppose lcd connector on mainboard is ok.
caspian believes the Vcore has no power so the CPU won't have power which I would believe need to be fixed before other issues show them selves (if any), I get no output to any display no LCD, no HDMI and no VGA.
now you did most the important tests and it is time to reach a conclusion.
the following voltages are missing on the board:
GPU_CORE, CPU_CORE, GFX_CORE, +1.5VSDGPUP
any advice and suggestions will be appreciated.
i see sometimes he write mv, but i see also 19mv where there sould be 19v so i think he write mv but he means volts. if so, 0.9 volts on cpu core is ok.
also:
1) cpu get hot when powered on?
2) vga nvidia get hot when powered on?
3) did u tried with an hdmi cable in the hdmi port ?
4) did u put a cmos battery in it ?
I guess the main problem is PU701 or the components around it. there may be a short there. This guess may be wrong though.
Now with the AC adapter disconnected, temporarily remove the CPU from the board and check resistance to ground on pins 25,26 of PU701. and also on PL703.
i see sometimes he write mv, but i see also 19mv where there sould be 19v so i think he write mv but he means volts. if so, 0.9 volts on cpu core is ok.
also:
1) cpu get hot when powered on?
2) vga nvidia get hot when powered on?
3) did u tried with an hdmi cable in the hdmi port ?
4) did u put a cmos battery in it ?
My digital meter said 000.9mV so that's what I've written, I hope I've done it right :-)
1) CPU gets warm when powered on a few times
2) VGA Nvidia chip is stone cold when turned on a few times
3) I have tried HDMI and VGA with no output
4) Have tried with and without cmos with no difference
Since testing PU502 I have been sometimes getting 1 beep then 7 repeated beeps, somtimes 2 beeps then 7 repeated beeps, sometimes 3 beeps then 7 repeated beeps, and sometimes 4 beeps then 7 repeated beeps.
I guess the main problem is PU701 or the components around it. there may be a short there. This guess may be wrong though.
Now with the AC adapter disconnected, temporarily remove the CPU from the board and check resistance to ground on pins 25,26 of PU701. and also on PL703.
Is that black on a ground point and red on the pin?
PU701
25 - starts around 6.75 k ohms and goes up to 6.89 k ohms
26 - 10.10 M ohms
PL703 - 12.16 M ohms
Did it again and it's now 5.56 M ohms and slowly decreasing
your resistance measurements are OK and do not show any short.
PU502 probably needs a reflow to get fixed that you can do it later.
are you skilled in SMD soldering?
It may be required that you replace PU701 later, but not now.
your resistance measurements are OK and do not show any short.
PU502 probably needs a reflow to get fixed that you can do it later.
are you skilled in SMD soldering?
It may be required that you replace PU701 later, but not now.
I'm good at soldering larger points but my iron tip is too big for SMD work, I may be able to get a smaller one if needed, I use a hand held loupe for close inspection.
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