X550jx black screen but cpu heating up

[questore]

Re: X550jx black screen but cpu heating up

Bios flashed from a same machine, but no change.
Removed u0303 and its surely faulty (0.8v dram_pwrok still)

I'm ordering replacement. Get back when replaced

[questore]

Re: X550jx black screen but cpu heating up

After replacing U0303 with this:
https://hu.farnell.com/nexperia/74lv...-ddd7-00001003
- DRAMPWROK is now 2.45V
- CPUPWROK és still 1v.

Whats next? DRAMPWROK resistance to ground is 1.17KOhm so its not sorted. Why is it still low?

[questore]

Re: X550jx black screen but cpu heating up

Ok I have read some intel startup sequence thread and figured out the following, PLEASE let me know if I'm right or wrong:
- DRAMPWROK should be larger than 1.05 so v2.45V is - GOOD
- CPUPWRGD 1.05v - GOOD
- PLTRST and BUF_PLTRST 3.3v - GOOD
- CPURST 1.05v - GOOD
So assuming South bridge and CPU is good and communicating. Right?

Next step would be to know if CPU is reading BIOS. Then Starting RAM How can I know that??? HELP NEED.

[questore]

Re: X550jx black screen but cpu heating up

PM_RSMRST = 0.045v

Is my BIOS corrupted? HELP

[stingerchamp]

Re: X550jx black screen but cpu heating up

If rsmrst# is not high it means KBC is not communicating with bios chip

First flash bios chip but If problem not resolved, first check KBC is working properly by checking it's requirements if ok then you have to programme KBC as well if programme able

For correct me region match

[questore]

Re: X550jx black screen but cpu heating up

If rsmrst# is not high it means KBC is not communicating with bios chip

First flash bios chip but If problem not resolved, first check KBC is working properly by checking it's requirements if ok then you have to programme KBC as well if programme able

For correct me region match

BIOS FLASHED and PM_RSMRST is now 3.3v
Problem still the same. Black screen.

How to proceed?

[stingerchamp]

Re: X550jx black screen but cpu heating up

Every mb has different signal routine but anyhow

Confirm again ec_on

Confirm SLP_s5# which is always state
Slp_s4# Which is sus state for ram
Slp_s3#. Which is run state for GPU and vccsa etc

[questore]

Re: X550jx black screen but cpu heating up

- EC_RST 3.27v (I do not know if this is what you mean by EC_ON)
- SLP_S3 3.3v
- SLP_S4 3.3v
- SLP_S5 3.3v

[stingerchamp]

Re: X550jx black screen but cpu heating up

In some cases it is written as Suson or mainon

First check if CPU is giving signal to ram

Dramrst# it is same as your ram voltage 1.35

Check gfx supply voltage around 0.45voltage and CPU core voltage
Then check ram section

Ram coil voltage 1.35 v for DDR3L
Ram vtt voltage at ram slot pin= half of 1.35
Ram SPD voltage 3.3v




If you are getting these voltage then check with DSO
Rtc clock generated or not
If all ok

Just remove CMOS cell for 30min and put it back and turn on

Btw you have a power sequence diagram which voltage step is missing did you check from 24 to onwards, check step by step do not skip

[questore]

Re: X550jx black screen but cpu heating up

POWER SEQUENCE VALUES

1 +3VA - 3.3v / +5VA - 5V
2 PS_ON - 3.3v
3 +3VA_EC - 3.3v
4 EC_RST - 3.27v
5 3VDSW_ON - 3.3v
6 3VA_DSW_PWGD - 3.3v
7 DPWROK_EC - 3.3v
8 ME_AC_PRESENT - 3.3v
9 PCH_SLPSUS# - 3.3v
10 5VSUS_ON - 3.3v
11 3VSUS_ON - 3.3v
12 5VSUS_PWRGD - 3.3v
13 +3VSUS_PWRGD - 3.1v
14 PM_RSMRST# - 3.3v
15 PCH_SUSACK# - 3.3v
16 ME_SuspwrDnAck - 16 mv
17 PWR_SW# - 3.27v
18 PM_PWRBTN# - 3.3v
19 PM_SUSC# - 3.3v
20 PM_SUSB# - 3.3v
21 SLP_A# - 3.3v
22 SUSC_EC# - 3.28v
23 SUSB_EC# - 3.3v
+1.2VS - 16mv
24 1.35V_PWRGD - 3.3v
25 1.05VS_PWRGD - 3.3v
26 P_1.5VS_PWRGD - 3.3v

- CMOS battery removed for 1 day but no change
- VDD 0.9v (GFX??)
- Dramrst# 1.347v
- Ram coil voltage 1.35v
-

[stingerchamp]

Re: X550jx black screen but cpu heating up

Do power button voltage goes to zero when you press it

And what is +1.2vs where you have 16mv, is there spelling mistake?

[stingerchamp]

Re: X550jx black screen but cpu heating up

Is it Up0104ssw ic sO-8

[questore]

Re: X550jx black screen but cpu heating up

Power button voltage is constant 3.3V and does NOT goes down when i press it.

+1.2VS 16mv is not a spelling mistake. It is measured at R4602 but maybe it because U4601 area is completly missing from this kind of board by default.

What do you mean by "is it Up0104ssw ic sO-8" ? Please elaborate.

[stingerchamp]

Re: X550jx black screen but cpu heating up

It is a ldo switch ic which is generating voltage 1.2v etc check your power sequence diagram

Power button one side is connected to ground and other side connected to board circuit
It is a temp switch which connects 3.3v present at button to ground for 2 second means 0volt and then retains/becomes 3.3v again so it must go down for couple of sec. Check again.

If still same then try to turn on by shorting connector pins if y don't know then leave it

Reprogramme your KBC if it is reprogrammable and check

[emestee]

Re: X550jx black screen but cpu heating up

Power button voltage is constant 3.3V and does NOT goes down when i press it.

Does the resistance of the button change when you press it? Maybe it's just a bad button.

[questore]

Re: X550jx black screen but cpu heating up

Does the resistance of the button change when you press it? Maybe it's just a bad button.

Resistance to button does not change.
Its always OL. Could it be that a bad button does this.
If i remove the button and plug the power adapter then the laptop does the same as with button connected.
Laptop now does the following when i plug it in to AC:
Starts for 4 seconds. (Power +numlock+capslock led constant, then turnds off for 3 second and starts again, but this time only power+numlock lit constantly.
Cpu and pch os heating slowly and fan starts spinning.

[questore]

Re: X550jx black screen but cpu heating up

Is it Up0104ssw ic sO-8

It seems that 1.2v generator and all around it the board is missing all components so asuming its for another model.

ME_SuspwrDnAck 0v is still mystery.

[emestee]

Re: X550jx black screen but cpu heating up

If youve already pulled out the button then test it out of circuit and you'll know if it's bad. When the button is out, you should of course short its pads to see if you get a reaction.

[questore]

Re: X550jx black screen but cpu heating up

If youve already pulled out the button then test it out of circuit and you'll know if it's bad. When the button is out, you should of course short its pads to see if you get a reaction.

OK I was a fool Rechecked the power button switch circuit:

- when power button not pressed +3VA_BD is 0v
- when power button pressed then +3VA_BD is 3v for 1 second then goes to 0 again. Sorry for the mistake.

Back to square 1.
Why does it starts itself without pressing the power button?

[stingerchamp]

Re: X550jx black screen but cpu heating up

Check crystal oscillator

If you have DSO or oscilloscope check 32khz clock available or not and keep it checking for 10sec

Make sure voltage on rtc cell 3 voltage

If you have xtal clock for PCH check xtalin and out for 14mhz clock available or not