Latitude 6500 intermittent no boot, flashing num lock indicator

My Latitude 6500 has intermittent failure to boot which typically ends with the caps lock and scroll lock indicators lit, and the num lock indicator flashing. If I let it sit awhile it will boot ok eventually. It seems like it might be somewhat tied in with the whole standby thing as it has done it when I've left it running unattended.

Thanks

 

What is the flashing sequence of the num lock LED? I would check the logs in the bios. There should be some type of event logged if you are experiencing post errors.

 

Sounds like a developing motherboard issue. The BIOS logs could be helpful as mentioned above. Try testing your RAM too.

 

Thanks for the replies.

The flashing sequence for the num lock LED is just a continuous flash off/on at the same pace.

How do I check the bios logs and ram?

 

Maybe have a look here (service manual):

ftp://ftp.dell.com/Manuals/all-prod...aptop/latitude-e6500_service manual_en-us.pdf

Theres a Diagnostic Light Codes During POST section on page 56, sounds like a possible processor
failure has occurred and reseating it or replacing it might help.
It might also be worth replacing your cmos battery first anyway to see if that helps and if you want you could use memtest for the ram, Hth

 

Running memtest now, no errors yet. How long am I supposed to let it run? It's at 250% coverage with no errors.

Removed and re-seated the processor.

 

It varies tbh, I usually leave memtest going over 12 hours, (but thats with overclocking).
If you want maybe leave it overnight just to see, although the likely culprit is your cpu, it cant hurt really.
It could also be your mobo though, so I'd probably be taking a backup but maybe youve done that anyway

 

If you're still on Warranty with Dell, I would call them first, of course.

If not, here is my story: My Precision M4400...which is very similar to the E6500....started doing the "flashing num lock" thing a few months back. Turn it on, would not complete the POST process and boot, just go to the flashing LED thing.

(I think it started after I updated to a new video driver or maybe it was when I was using a cheap DisplayPort to HDMI adapter cable. Whatever started it, it was frustrating me.)

I can't remember the exact flashing LED pattern, but I did look at the Dell diagnostic manual and it indicated a "processor failure"...and several experienced Dell users said it could be a bad MB too.
You can get the same indication when that happens.

At the time, I was in a hurry to get it back up and running. So, I reseated the RAM, and reseated the CPU...which Dell recommends...if you are capable of doing. (requires you to carefully disassemble and reassemble the laptop). But it did not change a thing.

I was about ready to buy a new CPU, just to see if that really was the issue. Then I read a thread on here about somebody who was having a similar boot problem. They said resetting the BIOS to factory default fixed the issue.

Basically, you just open up the notebook and disconnect the small internal battery cable that feeds a low current to the MB, which preserves the NVRAM holding the BIOS settings and the real-time clock. You just disconnect the battery...wait about a minute...then reconnect it. Then re-assemble the laptop and reboot.

After doing that, the system got past the flashing LED and I was able to go into the BIOS and reset things (like the date/time, etc)

System has worked fine ever since.

 

Ok thanks for the replies. memtest was fine, reseated processor, problem still persists and is getting much more frequent. Will try resetting bios.

 

This cable?