hi -- does the fan click on (in what seems like overdrive) when you have this sluggish response? i have had that happen with my 1505 and have posted in the 'portable - general hardware' section of this forum about it. if you search around in there for me, you'll see that has happened to several people -- all of which just had to a replacement computer. i'm trolling about a bit to see what is up as this seems to be happening to a fair number of users ...
my computer did it every time i started it "cold" -- like first thing in the morning. would take ~10 minutes to start, with fan cranking, then be incredibly slow. i would shut it down, restart, and all would be fine ???? it was only a few days old, so i called dell and have a replacement being sent to me this week. as you can see from the other posts i have made in the 'general hardware' section, other users who have had this have all had to return their computers.
i'm trying to figure out how to get dell's attention to these posts. it's obviously showing up on several machines and would be nice to get some real tech support to see how widespread this really is.
I found out what is wrong. It is a thermal sensor that is not functioning correctly. It probably send a false signal to indicate that the CPU is extremely hot, therefore the fan goes on and CPU switch to low speed, some of the cache may also shut down. This is the reason it is incrediably slow. You can prove this by following the below steps.
When you 'cold' start the computer, press F12. Then get into the 'diagnostic'.
The program will run on itself to test CPU, memory, etc, let it finish. However, this may take up to 1 hour since the CPU is running on low speed (you should hear the fan is quite noisy)
Once it finish testing the memory, go to 'custom test' and select testing 'sensor'.
you will see sth like sensor temperature is out of range and test 'fail'
I called Dell support, they are willing to send me an exchange computer. But since so many people here have this problem, I feel not comfortable to have this Inspiron 6400 anymore. So I just return the computer and buy some other brand.
This is quite annoying problem and took me so much time to figure out.
i too talked with tech support last night. i was able to get one of them to look at these posts (for your item plus the few with the 1505 units). he indicated he would escalate this to the proper channels. don't know if that helps, but i'm pleased that dell will investigate this further.
I have two 6400's, one a month old and one less than that, and both do it.
I'm glad to hear somebody else has the problem, I spent so much time trying
to figure out what was going on.
The newer one hasn't done it recently, but the older one is pretty regular.
Maybe they differ in how cold it has to be for the temperature sensor to
kick out of range.
Same symptoms exactly. High fan speed, 100% cpu utilization for a couple hours,
ten minutes to a desktop. Rebooting fixes it.
The house cools down to 55 degrees F overnight, which perhaps raises the odds
of the problem turning up a little, on the first boot of the day.
The things are assembled in Indonesia, which maybe isn't very cold, so the
tests are missing it.
I received a great response that I think identified the problem- faulty temperature sensor that sent the fan going full speed and did something to the cache. Good news is that Dell gave me a new one and it doesn't have the problem.
I put my two 6400's in an unheated bedroom (48 degrees F) for an hour and they both instantly fail the thermal sensor diagnostic test on the diagnostic CD.
The CPU thermmistor reports 0C (which is out of range, being 10C-100C) but
the ``Other thermistor'' and the Video Thermistor and the SODIMM Thermistor
all report 255C, which I guess accounts for the fan!
Unlike the normal case, it's not fixed by a reboot. I guess in cold air the
fan keeps it cold. In a regular room, rebooting fixes it.
Were there a huge number of these things produced with the error? It would seem
so.
I'd rather keep the same machines if possible. It takes a long time to set them
up with what I want on them. Maybe some software fix to ignore 255 at bootup
or something would fix it.
FIXED! BIOS version was V10, downloading V12 fixed the problem.
Apparently they used the fix outlined above, just ignore the 255C temperatures.
I cooled down both I6400's as before, and both came up fine with V12.
The diagnostic for the CPU thermistor still failed (out of range, 0C with a legal
range of 10C-100C) but the other three thermistors all passed, meaning they're
ignoring the 255's.
The too-cold thermistor of course wasn't the problem, so the fix works. You
still get a diagnostic fail from it, though, which someday they may want to clean up.
Raymond1998
3 Posts
0
December 5th, 2006 06:00
clarkwgriswoldi
8 Posts
0
December 5th, 2006 11:00
wbob007
34 Posts
0
December 6th, 2006 17:00
wbob007
34 Posts
0
December 6th, 2006 18:00
clarkwgriswoldi
8 Posts
0
December 6th, 2006 18:00
clarkwgriswoldi
8 Posts
0
December 6th, 2006 19:00
clarkwgriswoldi
8 Posts
0
December 6th, 2006 22:00
Raymond1998
3 Posts
0
December 7th, 2006 04:00
I called Dell support, they are willing to send me an exchange computer. But since so many people here have this problem, I feel not comfortable to have this Inspiron 6400 anymore. So I just return the computer and buy some other brand.
This is quite annoying problem and took me so much time to figure out.
clarkwgriswoldi
8 Posts
0
December 7th, 2006 11:00
wbob007
34 Posts
0
December 7th, 2006 13:00
clarkwgriswoldi
8 Posts
0
December 7th, 2006 14:00
rhhardin
8 Posts
0
January 21st, 2007 19:00
I'm glad to hear somebody else has the problem, I spent so much time trying
to figure out what was going on.
The newer one hasn't done it recently, but the older one is pretty regular.
Maybe they differ in how cold it has to be for the temperature sensor to
kick out of range.
Same symptoms exactly. High fan speed, 100% cpu utilization for a couple hours,
ten minutes to a desktop. Rebooting fixes it.
The house cools down to 55 degrees F overnight, which perhaps raises the odds
of the problem turning up a little, on the first boot of the day.
The things are assembled in Indonesia, which maybe isn't very cold, so the
tests are missing it.
clarkwgriswoldi
8 Posts
0
January 21st, 2007 20:00
rhhardin
8 Posts
0
January 21st, 2007 23:00
The CPU thermmistor reports 0C (which is out of range, being 10C-100C) but
the ``Other thermistor'' and the Video Thermistor and the SODIMM Thermistor
all report 255C, which I guess accounts for the fan!
Unlike the normal case, it's not fixed by a reboot. I guess in cold air the
fan keeps it cold. In a regular room, rebooting fixes it.
Were there a huge number of these things produced with the error? It would seem
so.
I'd rather keep the same machines if possible. It takes a long time to set them
up with what I want on them. Maybe some software fix to ignore 255 at bootup
or something would fix it.
rhhardin
8 Posts
0
January 22nd, 2007 15:00
Apparently they used the fix outlined above, just ignore the 255C temperatures.
I cooled down both I6400's as before, and both came up fine with V12.
The diagnostic for the CPU thermistor still failed (out of range, 0C with a legal
range of 10C-100C) but the other three thermistors all passed, meaning they're
ignoring the 255's.
The too-cold thermistor of course wasn't the problem, so the fix works. You
still get a diagnostic fail from it, though, which someday they may want to clean up.
Anyway, download V12 BIOS.