Inspiron 5100 won't turn on

[bitTRL1000]

So here's the story: My Dell Inspiron 5100 is about 3 years old now. Just the other night I was using it when I got the Blue Screen of Death. It indicated that System.sys caused the error. So I manually turned the laptop off. When I tried to turn it back on I only got halfway through loading windows before it shut off. I tried again and it wouldn't power on for more than 2 or 3 seconds before beeping once and shutting off. I then gave up for the night.

The next night I was able to start up the computer and it automatically went into the Dell system test software. I had it run a system test, and the only thing it mentioned wrong was that the CPU fan was running at a different speed then expected (probably 4000 RPM instead of 5000 RPM). After it finished I got into windows, but only for a few seconds before BSOD again. Similarly, it wouldn't even get to loading windows afterward.

As it stands now, when I push the power button, the CPU fan starts spinning, I get a LED light for power on, but then it shuts off after about 3 seconds.

Here's what I've done: I've removed the CPU fan assembly and dusted it with canned air. I removed the hard drive, secondary memory stick, PCI cards, DVD drive, and battery. It still will not turn on for more than 2 seconds. I tried placing the secondary memory stick into the primary slot, in case the primary stick was defective, but there's no change.

So here's what I'm thinking: Maybe the CPU fan works fine, but the 3rd lead that is used to report the speed of the fan is defective. If this is the case, the laptop would be turning itself off because it thinks the CPU fan isn't spinning, when it in fact is. Other than that, I'm out of ideas. Any suggestions? I don't think it's a fried motherboard because the problem got progressively worse. And it can't be an overheating issue because I can't get it to power on for more than 2-3 seconds even after it's been sitting for hours.

[Ob1]

sounds like the the processor could be overheating and causing the system to crash. maybe try removing the Heat sink and reapply some thermal paste to see if that fixes it.

try booting to a cd and run memtest86, do one stick at a time to see if the mem is faulty.
http://www.memtest86.com/

iMO, if the 3rd wire is faulty that controls the fan speed then to me the fan would just stop spinning all together.

[bitTRL1000]

Thanks for taking a look at my post.

It can't be overheating, because even when the laptop is completely cool it will shut off within 2-3 seconds after turning on. That isn't enough time for it to overheat.

And I can't get it to POST or boot at all, so running memtest, at least on this laptop, isn't an option.

AFAIK, the fan only requires the red and black wire to spin; it's the white lead that transmits RPM data.

[glc]

There should be more than one fan in that laptop - check them all.

[bitTRL1000]

The service manual (http://support.dell.com/support/edoc...mb.htm#1084976) only shows the "micro-processor thermal cooling assembly, which I know spins up when I push the power button.

I appreciate the help guys. I'm probably just going to order a laptop to destop HD adapter so I can get my data, then scap this thing for parts on ebay.

[Ob1]

i believe that the Inspirion 5100/5150 series have been nothing but problems for most people.......

[Klutz_atlantis]

Hello:

As an owner of a 5150 I can tell you that this model is the worst. As my first, and, thus far, only Dell purchase it has made me leary of the type of products Dell sells. The number one issue with this model for me was HEAT and the faulty battery pack was a close second. If fact there is a lawsuite that was filed against this model to get certian issues fixed. Here is some info:

http://http://www.blaptops.com/news/...inspiron-5150/

My 5150 is now dead, and quite honestly, even though I can get it repaired at little or no cost, I don't even want to deal with it. That machine was of poor quality and I can't justify getting it serviced, as I would rather purchase one of better quality.


I know this was only one bad apple, but you know what they say about first impressions and such.



Klutz

[glc]

My next door neighbor has a 5150 and uses it every day as his primary business computer. It hasn't been that bad - the hard drive developed a few bad sectors and we caught it in time, and it overheated and shut down once - an air blast fixed that, a LOT of dust came flying out. Yes the thing runs quite hot, it does have a desktop processor in it. He uses it for CAD and it crunches through it quite nicely.

[kilgoretrout]

I have a 5160 that runs very well. No problems in over two years. Perhaps they cleaned up their act from the 5150.

[Klutz_atlantis]

I guess I just bought the wrong laptop at the wrong time. Now that I'm doing research to possibly purchase a new one I've learned my lesson to say the least...going to purchase something tried and true and do extra research into possible issues with the models I'll select. Once I narrow it down to 3 or 4 I'll post on the forums for some user input.

I'm glad some people actually got a decent 5150, because when mine worked it was great...but with so many people haveing an issue with that model and from first hand experience there were definately some lemons. Just my bad luck of it being my first Dell purchase.



Klutz

[Ob1]

my first dell laptop was a piece of crap, my first laptop was the inspiron 5000e, and i had nothing but problems with that one. i had to have two motherboards replaced twice, the keyboard broke once, the hard drive failed once, and the bottom part of the case broke twice. all that happened within 3 yrs, luckily i had the extended warranty. i was a little discouraged about dell products, but i took a chance an bought an inspiron 8600 and have had great luck with this one. i have yet to have one thing break on it (knock on wood) and i have had this laptop for over 2 years now.

i think dell puts out good products overall but occassionally runs into a few problems with a few of there models, that unfortunately can be catastrophic, like my 5000e.

[Matt_Smi]

I used to work as a Dell field tech and used to service these all the time (not as much as D600s though). I used to replace a lot of motherboards on them, but I also replaced a lot of fan/heat sink assemblies. Like GLC said this model uses a desktop processor, but I am pretty sure the reason a lot of them overheat is because the thermal paste they used on this model is crap. Just about everyone I took them always had barely any paste it is was always dried up bad. In fact you have to be very care taking the heatsink off because most of the time the processor is stuck to it and you will rip it right out of the socket with it stuck to the HS. I recommend unlocking the CPU socket, then lifting the heatsink straight up and out, that way if the CPU comes out with it you won’t break any pins.

[glc]

Matt, how hard is that to get out in case I need to redo my neighbor's? Just remove all the "K" screws and lift the keyboard or is there more to it?

[Matt_Smi]

Originally Posted by glc Matt, how hard is that to get out in case I need to redo my neighbor's? Just remove all the "K" screws and lift the keyboard or is there more to it?

To get the heaksink assembly out? You actually have to remove the palm rest, if you take the keyboard off you will be able to see the heaksink, but you will not be able to take it out. So you pretty much have to remove every screw you can find on the bottom, as well as the LCD (don’t forget the two screws on the back where all the inputs are), and of course the keyboard will need to come off, which is four screws once you pop the keyboard bezel, there is also a heat shield under the KB which needs to be taken out, there is just one screw. Basically you will need to remove these components…

- keyboard bezel
- keyboard
- LCD
- Heat Shield
- Palm Rest

Then you will be able to take the HS out.

[glc]

I think I remember having to go through all that on a similar Latitude to change a motherboard once. I was just hoping it wasn't that deep. Dell only paid me 55 bucks to do it - onsite - what a waste of time.