Laptop Mobo failure

[xxsilk109xx]

I am working on this compaq presario f500.
The lady brings it to me and told me that it got hot on her and when she shut the computer down she could never get it to turn back on.

When I plug it in and hit the power button, the lights come on but there is nothing on the screen, not even a flicker of light. The hard drive sounds like it makes a little noise but then stops and the fan never comes on or even turns at all.

I have taken the memory out of it and it does not beep or post when i turn the power on.

Safe to say the mobo is fried in this thing?

 

[xxsilk109xx]

59 views and no comments?

 

[FooseSB]

Definitely sounds like it's possible the mobo may be cooked, but you may want to see if you can round up another power supply and try it, if you haven't done so already.

 

[ridgefieldpc]

yeah it's kind of hard to tell. Usually it is a fried mobo, but I would try swapping parts to be sure. CPUs rarely go bad so try swapping the ram. then again it could also be the CPU if it got hot on her maybe it was clogged with dust or maybe the fan failed and the CPU overheated. So try swapping that if you have one.

Otherwise I would cover my butt and tell her it is the motherboard with possibly the CPU as well.

 

[xxsilk109xx]

Thats what I was thinking, ok thanks everyone for your input.

 

[repairit]

I currently have a Compal FL90 that has similar response when I tried to replace the video card. With the original card, I got multi color vertical lines with a white background on the screen. When I replaced the card with a new one, I got a power light, a couple beeps but no fan and only a second of hard drive spin, then it shuts down, no video at all. I think I got a DOA card, but am still trying to figure it out while I wait on the RMA reply.

 

[Comtech Solutions]

You've tried starting it with just the ram, cpu and fans? Can you get into the BIOS? If yes, plug in your POST card and start looking up BIOS codes. I had one the other day that had the same symptoms, but worked fine once the CD player was unplugged.....

 

[xxsilk109xx]

Well I have even gone as far as taking the ram out completely and there are no beeps from the mobo, the fan spins for maybe 10 rotations then it stops.

 

[Platte Computer Repair]

The following symptoms apply to Compaq Presario F500 notebooks:
*The notebook does not detect wireless networks and the wireless adapter is not detected in the Device Manager.
*There is no video on the computer LCD panel or external monitor.
*The notebook turns on, power LEDs light up, but nothing is seen on the display.

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01480071&lc=en&dlc=en&cc=us&lang=en&product=3370444

From what I have learned it seems the video chip overheads and causes this issue. The warrenty has been extended for this issue 24 months from purchase date.

See link for complete details.
Hope this helps.

 

[zfrogz]

Have you tried removing the battery and unplugging it from the wall? I have see batteries cause problems like this before. Not sure why but sometimes I see laptops refuse to turn on until all forms of power have been removed for a minute or two.

If it has two sticks of ram (or you have some you know is good that you can pop in) try removing one of the sticks and try to boot. If no luck, try the other stick.

If that doesn't work, I would try to remove anything that is modular such as the hard drive, cdrom, internal wireless card / modem and try booting it again just to see if the bios screen pops up.

Inspect the motherboard for any burn marks or corrosion from water damage.

If that all fails, then it is probably the motherboard.

 

[kisk]

I wouldn't rule out a toasted CPU. I just had to replace a AMD Athlon 64 in a desktop and had the exact same symptoms as you: Power on, but no beeps or POST.

Luckily I had a similar CPU laying around so I could test it and verify it was indeed the CPU.

Intel CPUs will throttle themselves down when they start to get hot so they don't fry. Correct me if I'm wrong, but I don't believe AMD CPUs have this feature, and they run hot anyway right out of the box.

 

[zfrogz]

AMD's also have those protections built-in after the K6 I believe. That used to be a big issue back in the day but but it has been resolved.