powers on but no boot then turns off

"Hi, Here is a link to the manual for your unit--check out troubleshooting. You should replace the CMOS battery as a good first step. Good luck.

ftp://ftp.dell.com/Manuals/Common/inspir..."

"Pull the main battery, then hold the power button for about 30 seconds. That works for some Dell models.

The RTC battery (not CMOS anymore, just powers the clock) is prob on the back side of the mobo.

Update

Ok...just thought of something else. Is there a button on your battery with four or five LEDs? It'll be one of those soft membrane buttons. A fully charged battery will light all the LEDs lit for a moment when you press the button. One light is a discharged battery. Flashing lights: battery is deceased and needs recycled. A deceased battery can sometimes prevent the laptop from running, even with a good charger.

Is your charger working properly? Should be ~19V between the outer part of the plug (ground) and the inner ring of the connector. (don't mess with the pin, it's not relevant now) Can you try a different charger?

What often happens when the battery is dead due to a bad charger...it has just enough power to get the boot started then it runs out of juice, giving the symptom you're seeing."

"Hi,

Its seems like your Dell VGA has gone bad and is over heating the CPU this could be a heat sink problem. check if you can have it replaced.

Good Luck."

I would suspect the CPU has gone bad and is drawing a lot of current which is causing it to shut down. If the CPU is bad, nothing happens, no drive light flashing, no screen, nothing except maybe the HDD goes thru its self test. If it were the VGA card heating up something would happen b4 it shut down from a cold start.

I just got a Inspiron 8500 with this exact problem.