Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting Laptops, Tablets, and Mobile Devices
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 07-08-2020, 06:24 AM   #1
Lukosiukas
Member
 
Join Date: Jul 2018
City & State: Kaunas
My Country: Lithuania
I'm a: Knowledge Seeker
Posts: 76
Default Asus FX505DT

Hello, i need to identify a component. Computer do not turn on, this is getting extremely hot. No schematics or board-view available.
Markings on chip is :
W27
8
Attached Images
File Type: jpg 1.jpg (874.4 KB, 71 views)
File Type: jpg 2.jpg (313.9 KB, 85 views)
File Type: jpg 3.jpg (1.40 MB, 109 views)
Lukosiukas is offline   Reply With Quote
Old 07-28-2020, 06:51 AM   #2
Lukosiukas
Member
 
Join Date: Jul 2018
City & State: Kaunas
My Country: Lithuania
I'm a: Knowledge Seeker
Posts: 76
Default Re: Asus FX505DT

up, i dont want to pay 600euros for new motherboard
Lukosiukas is offline   Reply With Quote
Old 02-19-2021, 12:11 PM   #3
xweb
New Member
 
Join Date: Aug 2011
Posts: 5
Default Re: Asus FX505DT

same problem here... did you solve?
xweb is offline   Reply With Quote
Old 11-30-2021, 04:28 AM   #4
reformatt
Badcaps Veteran
 
reformatt's Avatar
 
Join Date: Feb 2020
City & State: Noosaville
My Country: Australia
Line Voltage: 240V 50hz
I'm a: Professional Tech
Posts: 818
Default Re: Asus FX505DT

I've just had one of these boards machines come through. The power adaptor immediately shuts down when connected.

Located the fault with voltage injection and thermal camera. The area in question by the OP is for CPU Vcore, and in my case was the AOE6932 dual FET to the left. Only one of the internal FET's had shorted, the other was ok. I usually find a dead CPU at the end of this scenario. The CPU measured a little over 1.2 ohms so I was not confident. But at least it wasn't a dead short. I didn't have a replacement at the time, so I took it off the board and saw what the other phase would do. Surprisingly I got 1V. Machine wouldn't fully start because of the missing phase, but there was hope.

So ordered it, and finally fitted the replacement AOE6932 today and machine is working fine. I have to assume the FET that shorted was the low side FET, not the high side as the CPU survived. I took the liberty to measure some volts on the coils for future reference. A little over 1 ohm seemed a little too low fpr Vcore, but there you go.
Attached Images
File Type: jpg FX550DT.jpg (574.3 KB, 44 views)
reformatt is online now   Reply With Quote
Old 12-01-2021, 01:19 PM   #5
caspian
Badcaps Veteran
 
Join Date: Oct 2015
City & State: Mainboard
My Country: Laptop
I'm a: Hobbyist Tech
Posts: 1,539
Default Re: Asus FX505DT

Thanks,
Is there any hot Mosfet now after the replacement?
How much hot is the CPU now?
caspian is offline   Reply With Quote
Old 04-15-2023, 12:12 AM   #6
trepachka
Member
 
Join Date: Oct 2022
City & State: Vernon Hills
My Country: United States
I'm a: Knowledge Seeker
Posts: 51
Default Re: Asus FX505DT

Hello, my motherboard is also Asus FX505DT. However, the boardview I have is for a different revision of this motherboard. I need help identifying both capacitors that are not part of the boardview I have and also appear to be shorted. There are several faults with this motherboard. I removed the super I/O chip and that short is gone. However, these two capacitors are also shorted. I am afraid the GPU is dead as result. Thanks in advance.
Attached Images
File Type: jpg 20230415_005737.jpg (250.2 KB, 15 views)
trepachka is offline   Reply With Quote
Old 04-15-2023, 03:08 AM   #7
Bonzas
Badcaps Veteran
 
Join Date: Jan 2018
City & State: Jawa Tengah
My Country: Indonesia
Line Voltage: 220VAC 50Hz
I'm a: Knowledge Seeker
Posts: 349
Default Re: Asus FX505DT

Quote:
Originally Posted by trepachka View Post
Hello, my motherboard is also Asus FX505DT. However, the boardview I have is for a different revision of this motherboard. I need help identifying both capacitors that are not part of the boardview I have and also appear to be shorted. There are several faults with this motherboard. I removed the super I/O chip and that short is gone. However, these two capacitors are also shorted. I am afraid the GPU is dead as result. Thanks in advance.

Maybe this
Attached Images
File Type: png 1.png (57.6 KB, 17 views)
File Type: png Screenshot_3.png (49.6 KB, 9 views)
Bonzas is offline   Reply With Quote
Old 04-15-2023, 02:34 AM   #8
Stevedb
Stevedb
 
Join Date: Feb 2018
City & State: Schendelbeke/ East-Flanders
My Country: Belgium
Line Voltage: 240v ac
I'm a: Hobbyist Tech
Posts: 523
Default Re: Asus FX505DT

How much resistance do you have. It is normal to have low resistance there it can be 1 ohm or so on newer gpu core
Stevedb is offline   Reply With Quote
Old 04-15-2023, 03:11 AM   #9
Stevedb
Stevedb
 
Join Date: Feb 2018
City & State: Schendelbeke/ East-Flanders
My Country: Belgium
Line Voltage: 240v ac
I'm a: Hobbyist Tech
Posts: 523
Default Re: Asus FX505DT

I think it is jut low resistance and not a short.how much resistance do tou have to ground?
Stevedb is offline   Reply With Quote
Old 04-15-2023, 09:42 PM   #10
trepachka
Member
 
Join Date: Oct 2022
City & State: Vernon Hills
My Country: United States
I'm a: Knowledge Seeker
Posts: 51
Default Re: Asus FX505DT

I am new to this and took the beep coming from my multimeter as a short. The resistance measures 3.2 Ohms. I am also attaching the image from the backside of either GPU or CPU (I am not sure which is which). Most of those capacitors also read about 3 ohms.

I definitely removed the short when I took out the super I/O chip IT8987E/BX.

A question: does this chip require reprogramming or can I just purchase one on eBay or any other place as long as the markings on the chip match?
Attached Images
File Type: jpg 20230415_223327_HDR.jpg (183.0 KB, 9 views)
trepachka is offline   Reply With Quote
Old 04-16-2023, 12:30 AM   #11
mcplslg123
Badcaps Veteran
 
Join Date: Jun 2015
City & State: siliguri
My Country: india
Line Voltage: 220vac,60hz
I'm a: Professional Tech
Posts: 5,524
Default Re: Asus FX505DT

Yes, IT8987E is programmable but with asus it'll program itself on 1st boot. Make sure the suffix after IT8987E matches.
mcplslg123 is online now   Reply With Quote
Old 04-16-2023, 02:18 AM   #12
trepachka
Member
 
Join Date: Oct 2022
City & State: Vernon Hills
My Country: United States
I'm a: Knowledge Seeker
Posts: 51
Default Re: Asus FX505DT

What about the resistance value on those capacitors I had mentioned? Is it expected for the resistance to be around 3 ohms? All mosfets I checked are OK. The main power rail is present but that's about it. No other voltage is there. That's why I tested the capacitors around the controller chip and they were all shorted to ground. I am ordering a new controller chip. I am hoping that was the problem.
trepachka is offline   Reply With Quote
Old 04-16-2023, 11:10 PM   #13
mcplslg123
Badcaps Veteran
 
Join Date: Jun 2015
City & State: siliguri
My Country: india
Line Voltage: 220vac,60hz
I'm a: Professional Tech
Posts: 5,524
Default Re: Asus FX505DT

Hey man, dont mess with those caps. These are low voltage rails and caps here could show as low as 1-2 ohms and that cant be considered short.
mcplslg123 is online now   Reply With Quote
Old 05-22-2023, 07:49 PM   #14
trepachka
Member
 
Join Date: Oct 2022
City & State: Vernon Hills
My Country: United States
I'm a: Knowledge Seeker
Posts: 51
Default Re: Asus FX505DT

After replacing IT8987E, I also found another fault with bq24780S chip. It was replaced as well and now I get 5v, 3.3v and 1.8v power rails. However, on power up, computer keyboard flashes keys non-stop and the notebook is not charging. Checking battery charging pin I only get 2.5v vs. 10v+ expected.

I am just wondering what my next step should be.
trepachka is offline   Reply With Quote
Old 05-22-2023, 10:43 PM   #15
mcplslg123
Badcaps Veteran
 
Join Date: Jun 2015
City & State: siliguri
My Country: india
Line Voltage: 220vac,60hz
I'm a: Professional Tech
Posts: 5,524
Default Re: Asus FX505DT

Locate the 2 dc-in mosfets and then measure voltage on pin1-4-8 of these fets and report back. Also mention the voltage on all pins of battery connector(without battery )
mcplslg123 is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2023
Powered by vBulletin ®
Copyright ©2000 - 2023, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 11:23 PM.
Did you find this forum helpful?