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Screen jerkiness (for lack of a better title)



8:36 pm on Dec 10, 2009 (gmt 0)

5+ Year Member

This problem just started about 2 weeks ago. There are several symptoms, but they all are related as far as I can tell.

Videos no longer stream smoothly, if at all. I can hear the sound, but the video moves jerkily (if at all). When I type things, such as in this box, the letters sometimes do not appear right away, the cursor freezes, then the letters pop in a few seconds later after I have typed a whole string, they appear all at once.

Also, when I drag windows, they do not move right away, if at all. Or they move a few seconds after I have let go of the mouse button. And lastly, windows do not become active every time I select them in the task bar, or they take a few seconds, sometimes 10 or more, to become active.

What I have tried to solve this: The RAM door was very hot, so I got an external belkin fan thing to set this laptop on and this keeps the ram really cool. Didn't help.

I was due for a reinstall of XP Home, so I went ahead and did that, and that has not helped. I have downloaded all the critical updates as far as I know, and installed SP3.

The machine is a Dell Inspiron 9400 Core 2 Dupo T7200 2ghz with 2gb Ram, ATI Mobility Radeon with 256 MB ram, and I upgraded the hard drive to a 320gb.

I suppose this could be hardware related, but just not sure. About a year ago, Dell replaced the motherboard, memory and fans, trying to solve a fan problem that I had. At any rate, as I said this just started about two weeks ago.

Thanks for any help you can offer.


9:07 pm on Dec 10, 2009 (gmt 0)

10+ Year Member

Shut it down. Leave it overnight. Does it still exhibit the problems from cold startup? If so, it's almost certainly overheating. I'd guess that there's no airflow over you graphics chip. Either a dead fan, or clogged airways. These laptops have metal grilles just inside the vents, and they can catch a lot of dust and fluff.

You can clean it yourself, but unless you're comfortable taking the whole thing apart (fascia and keyboard off, unclipping the wires going to the LCD etc.) you may want to leave it to a professional.


9:11 pm on Dec 10, 2009 (gmt 0)

5+ Year Member

Thanks. I have noticed that the fans seem to be running all the time lately. So I bet you are right. I may be keeping the RAM cool with the external fan, but not the graphics chip.

I should have said that yes, from completely cold startup, I have been able to stream videos and get smooth screen draws, but only for 5 minutes or so. I didn't think that the chip could heat up so fast, but I bet that is what is happening.

I watched the DELL tech repair the machine, so I think I can take it apart and see if the fan and air channel is blocked.


11:43 pm on Dec 10, 2009 (gmt 0)

WebmasterWorld Senior Member kaled is a WebmasterWorld Top Contributor of All Time 10+ Year Member

Start the task manager (right-click the taskbar) and check CPU usage.

The symptoms sound more like a software issue to me - if a chip overheats it crashes. When running on batteries, sometimes a CPU may slow down instead of operate the fan but when running on mains power this is unlikely.



12:24 am on Dec 11, 2009 (gmt 0)

5+ Year Member

Thanks Kaled. This is on plug in power when it happens. Before I reinstalled Windows, I was seeing 100% CPU usage a lot. That was another reason I wanted to do a reinstall. That is no longer an issue, but I am still having the video problem.

I'll try cleaning the air channel and report back.


1:03 pm on Dec 11, 2009 (gmt 0)

WebmasterWorld Senior Member kaled is a WebmasterWorld Top Contributor of All Time 10+ Year Member

High CPU usage usually means bad security software or rogue indexing software - that's where I'd start looking.

Slow typing response can be the result of spell-checking. For instance, if you have a dictionary installed in Firefox (as I do) then the echo of characters when typing can be erratic.



3:53 pm on Dec 11, 2009 (gmt 0)

5+ Year Member

The only security I have currently installed is Microsoft Essentials.

This morning I turned on the computer, and went to HULU. I watched about 2.5 minutes of a video before it started getting jerky. I heard the fan turn on at about the same time the jerkiness started. All the time I was running the belkin fan underneath. (also the internal fans make much more noise now than they used to, not a rattling or anything bad, just a whirring)

So I am thinking the graphics processor is overheating, and perhaps the new whirring sound is the air channel being restricted. This weekend I will be taking this thing apart to see what, if anything, I can see inside.

I pretty much solved the CPU usage problem with the reinstall of windows.


3:58 pm on Dec 11, 2009 (gmt 0)

WebmasterWorld Administrator mack is a WebmasterWorld Top Contributor of All Time 10+ Year Member Top Contributors Of The Month

This may help with further diagnosis. Try running an OS from a live CD. Just a simple linux distro should do.

If your system displays the same issues then it is almost sertaily a hardware issue, if not then it is likely to be somethign installed along with your current bootable OS.

The "jerky" screen issue is quite common if the incorect drivers are installed for your graphics card.



1:04 am on Dec 14, 2009 (gmt 0)

5+ Year Member

I took it completely apart and removed the video card and fan. It wasn't very dirty,but I blew out the heat sink fins and fan and made sure the fan spins freely.

Put it all back together and the problem is gone. Thanks for all the suggestions.


12:40 am on Apr 21, 2010 (gmt 0)

5+ Year Member

The problem came back, so I did more thinking and research. Also recalled what the Dell service tech did a year and a half ago. He replaced the mobo, but used my old processor. So the other day, I installed a temperture sensor program and my cpu was peaking at 180 F. It occurred to me that when he moved the cpu from one mobo to the other, he did nothing about the thermal paste.

I got some Arctic Silver 5, cleaned the processor and heat sink and put on the new paste. Now she runs like new! Maxes out at maybe 120 degrees when I do something really intensive.

Just thought it might be good to post an update for anyone with similar problems.

[edited by: bill at 4:12 am (utc) on Apr 21, 2010]
[edit reason] a little cleanup [/edit]


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