I have also had this problem twice on a Dimension 3100 ... the computer won't start up properly after working fine for months. 6 beeps on startup but no video. It mysteriously cleared up the first time just as I was calling Dell. Of course, it was still under warranty at that point! It happened again during the holidays, just when kids wanted to play some new games. It worked after I opened the case & looked for loose connections, even though I didn't find any. This IS a frustrating gremlin!
Jdzuegel, is there a pattern to the beeps ? If so, the system maybe trying to tell you an error code. Also do the diagnostic lights give an error code which could further help pin point the problem ? Click here <ADMIN NOTE: Broken link has been removed from this post by Dell> for an explanation of the beep and diagnostic light error codes from your model's on-line Service Manual.
I have a Dimension 8400 with the same problem. I also tried reseating the RAM. No help. I am hoping that another example of the same problem might give someone an idea.
I think it may be the BIOS. I was trying to troubleshoot a USB problem and several people suggested updating the BIOS. I downloaded the update but the computer locked on the "Windows Shutting Down" screen. I had to power off and now it won't boot.
I checked with my kids and this particular lock-up had occurred before so maybe it was the interruption of the download that hosed it. Like the original BIOS was disabled/deleted and the new version didn't complete the installation procedcure?
I also get 6 beeps - 4 and then 2. I can't find this in the beep code listing that was given in this thread. Is there a different code for 8400's? I don't know that it would do much good though, because I don't know what to do about most of the code explanations anyway.
I can't reproduce the problem now, since the computer is booting up fine. I can't say that I am not glad that the computer is working now, but it's a little unsettling not knowing why I received the beep codes & why/how it disappeared.
Jdzuegel, intermittent problems can be hard to find as you have found out. The best I can recommend is if this happens again take note of any beep pattern and check the diagnostic lights. Those two items may give you a clue as to the source.
Jbeatty6, your problem is a little different than what has been mentioned in this message thread. In your situation the system is hanging after a BIOS update which is not uncommon for the 8400 model. The cure for most of the people that experience the problem is to do a "hard" reset of the NVRAM which I have explained below. More than likely the reason why the system hanged during the reboot phase of the BIOS update was due to a Windows application running in the background or a USB device attached to the system.
With the machine unplugged from the wall remove the battery from the motherboard. Then with the machine still unplugged press the On button for 30 seconds to dissipate any remaining electrical charge on the motherboard. Then re-install the battery, plug the machine back into the wall and see if it will boot normally. You can click here <ADMIN NOTE: Broken link has been removed from this post by Dell> for additional information on how to remove the battery from your model's on-line Service Manual if need be.