We help IT Professionals succeed at work.

Check out our new AWS podcast with Certified Expert, Phil Phillips! Listen to "How to Execute a Seamless AWS Migration" on EE or on your favorite podcast platform. Listen Now


Samsung SyncMaster 170MP LCD Monitor Blinking

Medium Priority
Last Modified: 2013-11-08

I'm having a problem with my monitor Samsung Syncmaster 170MP LCD monitor. Everytime I'm on the Internet Explorer or on desktop while scrolling or moving the mouse, resizing and maximizing windows, switching programs on desktop bar, typing, anything that I do on desktop my monitor blinks (turned off for 1 second and then turned on again). Also sometimes I'm not even doing anything on the desktop (letting the computer idle for 10 minutes) and it also blinks. Sometimes after it blinks, the monitor shows me some garbled images like on Internet Explorer tool bars, Start Menu, etc. Strangely enough, it doesnt blink when I play 3D games. This is happened about a week ago, everything was working fine before.

This is what I have for my system:
- AMD Athlon XP 2400+
- Samsung SyncMaster 170MP LCD Monitor
- Leadtek A280 Geforce4 Ti 4200 8x
- ABIT KD7 Motherboard
- Soundblaster Live 5.1
- 512 MB DDR Ram (PC2100)
- Logitech Elite Duo Combo

This is what I already tried:
- Reformatting hard drive and reinstall windows xp
- Scanning for Viruses
- Set the Hardware Acceleration to None
- Install new drivers for my video card, monitors, keyboard, mouse, sound card, motherboard chipset
- Updating my windows using windows update and automatic update
- Declocking video card and cpu
- Updated my video card bios
- Switching the video card with Geforce 2
- Checking all the wires inside and outside my computer make sure they're connected properly

with no luck I still cant fix the problem... My best guess right now, everytime the screen shows garbled image, the monitor will refresh itself and that's what causes to blink, but I could be wrong.

Thanks in advance for your help.
Watch Question

I'm pretty sure you've already isolated the problem.  Check the system with a CRT monitor as a final confirmation that your monitor is bad.  If the monitor is still under warranty get another one or get it repaired.  It may not last much longer.

There is one other very remote possibility.  Third party mouse and keyboard drivers can sometimes cause bizarre problems - especially Logitech.  Remove any third party mouse and keyboard drivers and software then try a standard PS2 mouse and keyboard and let windows load it's native drivers.


I believe this may have something to do with your DirectX configs.  Run the DirectX diagnostic tool.

Testing DirectX ComponentsYou can test Microsoft DirectDraw and Direct3D on each monitor attached to your system. You can also test DirectSound on each wave output device, and DirectMusic on each music port.

To test a DirectX feature
Click the Test button on the appropriate page.
Read any messages that appear.
Watch or listen to the tests.
Let each test run until you see a message asking if the test was successful. If you respond No, no more tests are run.
In the case of DirectMusic, there is a single test. Click OK when you are satisfied that the music is or is not playing correctly.

You can test Microsoft DirectPlay functionality on any available service provider.

To test DirectPlay
On the Network page, click Test DirectPlay.
In the DirectPlay Test dialog box, type a user name and choose a service provider.
Select Create New Session, and then click OK.
If you have chosen a modem connection, click Answer in the Modem Connection dialog box to put the modem in auto-answer mode.
Now run the Microsoft DirectX Diagnostic Tool on another computer that can establish the selected connection with the first computer.

Click Test DirectPlay.
Type a different user name.
Choose the same service provider.
Click the Join Existing Session button, and then click OK.
For some types of connection, you might be asked to provide more information, such as a telephone number. For a TCP/IP connection on a local network, you can leave the text box blank.

In the Session List containing the name of the session you created on the first computer, select the name of the session.
Both computers should now show a chat dialog box. Type a message in the input box on one computer, and then click Send. The message should appear in the scrolling area of the chat dialog box on both computers.


Little updates for what I tried:

I managed to borrow Samsung SyncMaster 750s CRT monitor off my Friend. Apparently this doesnt solve the problem either. I'm surprise that the CRT monitor actually blink the same as my LCD monitor. Right now I'm positive it wasnt neither the monitor nor video card problem.

I also uninstalled the third party software from Logitech (Mouseware and iTouch) and still no luck.

I checked the dxdiag as Slink9 told me and no... I dont find any problems with my direct x 9.0b.

Check the settings on your video card.  Make sure they are correct for the monitor.  Verify that you have the latest drivers from the manuf web site or www.driverguide.com
This could be a known problem that has been fixed wiht a driver update.
Set your video type to VGA.  Does it happen now?
Swap the video card for a standard PCI VGA and see if it still happens.
Play with the video acceleration and see if that makes a diff.

Go into display properties, screen saver and set the monitor to always on. Go into settings and advanced and to monitor and change refresh rate to 75khz or adapter optimal. Resize your screen to 640 and then to the highest allow by the interface probably 1280x1024. Accept the changes and then go back in and set it to your preferences. Restart system. Enter into BIOS, reset to factory defaults. Change settings as you prefer by leave any VGA/Display settings alone. Overclocking the cpu and memory can also produce your result. One other issue may be with a surge protector, UPS or bad electrical outlet.
This is not a common problem.  When I have encountered it its almost always the monitor.  I did some research and there is one dominate cause (other than the monitor):  Power settings.  Most have had success by disabling All power management/saving features in the BIOS and Windows.

The other causes are the refresh rates and bad video cards - in that order, and those have already been covered.

If you haven't solved the problem yet try disabling all power management features in Windows and the BIOS.  Worth a try.

Top Expert 2012

You may have a faulty video card.  Swap it with one that works and see if you still get that behavior.  Then try the troublesome card in another system, to be sure.


Another update on what I tried:

- Reset the bios into default (using the motherboard switch)
- Format my Hard disk
- Reinstalling Windows XP Proffesional once more (reinstalling the latest drivers and updates also)
- Disabling DMZ zone from my DLINK 704-UP Router
- Changing Resolution (640x468, 800x600, 1024x768), Refresh Rate (60Hz-75Hz), and Depth Colour (16bit - 32bit) on my computer.
- Switch the video card with my friend's Geforce 4 MX (still blinking) and tried my video card on my friend (it works flawlessly on my friend computer)
- Changing Power supply cable that connects to my PC
- Changing the outlet plug from my UPS
- Changing the outlet plug to the wall (without UPS)

Strange things that happened:

- After I reinstalled Windows XP (I havent touch anything from the windows), during the welcome screen it blinked
- Sometimes after it blinked, my computer restarted by itself

Additional information:

- I never overclocked my CPU, Memory, and Video Card
- I usually turned on the computer for 24/7 for server purposed with monitor off.
- It only happened in desktop, never happened during windows installation, 3D games, or other application that required full screen.


Could you tell me how to disable the power management from the bios and windows xp fully? I just wanted to make sure if I disable the power management correctly.

Again... I still dont have luck to solve this problem.



I made a typo on the "What I tried" section, it's suppose to be:

- Changing the Power Supply cable from my PC on different plug on my UPS.
- Changing the Power Supply cable from my PC to the wall.

Start-Control Panel-Power options
Set everything to never turn off and disable hibernation

I don't believe that will be your problem, though.  One thing that I don't think you have tried - electrical interference.  Move the computer and monitor to the other side of the room or another room entirely.  Now plug it back in and see how it does.
I once had a monitor that would pulse.  I tried everything until I finally go frustrated and moved the monitor over some.  It had an effect on the problem.  We ended up moving the desk to the opposite side of the room and the problem disappeared.  There was some kind of electrical interference coming frm that wall.  Maybe there was an electrical cable wrapped around a steel beam or something like that.
Top Expert 2012

Have you changed the video cable itself?  If it's not the video card and it affects the LCD and the CRT, there has to be something in common.
Plucking at ideas here, but have you tried changing your power supply (not the UPS)?



Little update:

- Changed CPU fan from stocked fan to Thermal Take Extreme Volcano 12
- Moved the computer and monitor to the other side of the room

again... no luck... lol...

Additional information:

- I recently changed the power supply to 350 Watt Enermax Power supply (2 months ago) and it's working flawlessly before (no blinking). I never have blackouts, electrical noises, etc happened to my power supply since the UPS usually will take care of those stuff.

- I will try moving the computer downstair tommorow and see if the problem will be fix.


- My friend have an additional 250 watt powersupply; but, do you think it will handle my computer or suggestion? I have 4x 80mm fans, geforce 4 ti4200 8x, amd athlon xp 2400+ and Thermal Take Extreme Volcano 12 fan. I dont really have money to afford another one. I'll buy another power supply as the last chance.

- For Callandor: well I tried to change the monitor from LCD to CRT. My Samsung Syncmaster 170MP LCD and Samsung Syncmaster 750s CRT monitor have different cable to connect to my VGA card. No luck... They both are blinking when I go to the desktop. Is it what do you mean by changing the video cable?
Top Expert 2012

Yes, that's what I was looking for.  The Enermax power supply is a good one, I use it myself.  I would try moving the setup, as suggested, in case it's interference.  This is a really strange problem.

I don't see where you have tried memory from another system. If your getting a reboot or shutdown I would stop doing everything else until you can try a different stick of memory. If you have two sticks try removing the first stick in the sequence of DIMM slots. Your errors seem to be occurring in the bottom half of your memory range. I saw that you swapped out for a GeForce 2 and ergo the video checks good. The monitor checks good since the error replicates from flat panel to CRT. I am will callandor on the enermax, good product.


I havent tried anything new yet right now but I think this information might be helpful finding the problem. This problem started like around 8 days ago when I was surfing on the net and it blinked once. Then the next day it blinked around 2-3 times in a day. Somehow this problem is getting worse and worse and right now, my computer will blink like every minutes when I use the desktop. I also tried to shut down for the whole night (around 6-8 hours) then turn it on, somehow it fixed for the first 15 minutes and then it started blinking like crazy again. As I mentioned before I tried declocking my CPU and Video Card, open the case, check all the fans (they're working), and none of them working.

I'll try to do several things tommorow and hopefully it will works.

This actually sounds like a heat issue.
Try running it with the case open and a small room fan blowing into it.  See if that helps.  If so, it is definitely a heat issue.
You may also want to try backing the system down to a bare minimum system.  Only use the cpu, memory, STANDARD PCI video, and floppy.  Let it run for a half hour.  No blinking?  Shut it down and put one piece at a time back in and let it run for a half hour until it starts blinking again.  When the blinking resumes, it was the last piece you installed.
Note that you should test this with a PCI video card.  I am still guessing that there will be no problems and you will be able to rebuild the entire system but the blinking will resume when you put the AGP video back in.  I don't see a reference to trying a plain PCI video card.


OK another update what I tried:

- Turned off all the Power management (I should've mentioned this earlier)
- Brought the computer downstair and plug it to the wall
- Open up the case, put large fan besides it (turned to maximum), maxed my Extreme Volcano 12 fan (from 4500rpm to 5500rpm) so that the temperature from 45 C dropped to 30 C

and you guess it... nope it doesnt work... still blinking...


- OK, I dont really have much supply here. Assume if I have and test my computer with PCI Video card and it works fine, does it mean my motherboard broken (the AGP slot)? and the only way to fix this is to replace the motherboard? or there could be still many possibilites? And again I dont have blinking problem in DOS (So I cant just boot up the comp and let it be on DOS) it's only in Windows XP Professional Desktop.

The fact that it doesn't happen in DOS would indicate that it is something with the resolution settings.  Have you changed the settings around as mlynch suggested?  Have you verified that you have the latest version of the video drivers?
This definitely appears to be something with the video, either in the settings or the hardware communication.  If a PCI card does not have these problems it could indicate that your AGP card is malfunctioning.  Can you slow down the AGP multiplier?


yes I did...

I played around with the refresh rate, changing resolution, depth colour, disable all the features from bios and no.... I cant slow down my AGP multiplier with my Geforce 4 from bios; however, with Geforce 2 I can slow it down through the bios and I did that and it's still blinking.

I downloaded my video card driver from Nvidia.com official website. The date for my driver is April 1st 2004. I also tried from the Video Card manufacture website which is Leadtek driver and their latest driver is November 17th 2003. Right now I'm using the driver from Nvidia official website. I also updated my monitor drivers from microsoft website. Their latest is Febuary 22nd  2002.
Unlock this solution and get a sample of our free trial.
(No credit card required)

This is the most intersting case I ever met.
Let me know if you resolve it.
I guess you might have some virus that either reside in your HDD 0 sector or in the CMOS chips.
Do the following to see if that will help.

1. Open the case , clear the CMOS by jumpers. restart the computer and don't start the syste,
2. Enter the BIOS setup program to see if it can format the hard disk from there.
3. if the BIOS can not do, find a clean bootable 3" disk and then fdisk your HDD and format it there.
or use some special tool to clean the 0 sector of your HDD and do the lowlevel format. It won't hard your disk it was fine.
4. Reinstall your system , it should work.

From all the words above, I don't think this is a hardware problem.
Don't try more things to scew them up. This brought your real trouble.

When any monitor that you have hooked up to the computer blinks, does the power LED on the monitor change color, green to amber and back to green after blinking? I think you have isolated your problem down to the BUS (CPU, MEMORY, MOBO). I doubt that your video card is the problem since you swapped them out as well as monitors. If the monitor LED changes I believe your experiencing power loss to the AGP slot. Double check your power supply. Here's how:
ATX PS Testin procedure:

1. Remove all connectors to peripherals except the HD
2. Revmove the 20 pin ATX power connector from the systemboard
3. Use a plastic coated twist tye, doubling the bare wire ends.
4. Insert one end of the twist tye into the black wire socket next to the green wire
5. Insert the other end into the green wire socket
6. Use a digital multimeter grounding the black probe into any other black wire socket
7. Test each of the red wires to make sure they are within .1 of +5.0vdc
8. Test each of the orange wires to make sure they are within .1 of 3.3vdc
9. Test the purple wire to make sure it is within .1 of +5.0vdc
10. Test the yellow wire to make sure it is within .1 of +12vdc
11. Test the white wire to make sure it is within .1 of -5vdc
12. Test the blue wire to make sure it is within .1 of -12vdc

If these test good and the HD continues to spin steadily throughout the test your PS has a 99%
probability of being good. If the HD fluctuates during any part of the testing or even
powers off, replace the PS.


It seems my old motherboard have some problem in the AGP slot. I took the shortcut by replacing my old motherboard (ABIT KD-7) to a new one (ABIT NF-7) and the problem is fixed.

Thank you guys for helping me fix this problem.

That was a "nail on the head" answer.  Why a B?


Whoops sorry... I was meaning to give you an A but I guess I was very tired and made a wrong click....

I'm really sorry about that...

Not a problem.  I like to see Bs explained, even if it is a "wrong click" explanation.  Thanks.
Unlock the solution to this question.
Thanks for using Experts Exchange.

Please provide your email to receive a sample view!

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.