I have a dead machine. It is under warranty, however, I want to be educated. I get two green flashes followed by a pause, and then 7 more. Dell support said it was a memory error, so I reset the RAM, but it didn’t help. The place I bought the machine from said that they replaced the motherboard right before they sent it to me. I told this to DELL, but they see no record of it. The are overnighting a motherboard and a on-site repair guy is coming out to fix it. So, the question is, does this sound like a MB issue? No sound, beeps or fans, and no lights on the keyboard. all I get is a flashing on-light. Nothing onthe monitor, either. I could never just reboot. Each time I had to press F1, but ass long as it worked, I was fine with int. I shut down last night, but this morning is had a task open, so I had to kill it. When I killed the task to shut it down, the computer powered down and that’s all she wrote.
Whats the motherboard number on it? you can probably find codes on dell support site. I doubt its the ram because even with no ram you should get a post. The fact that you don’t means its either the board or the psu, a psu sounds more like a viable reason.
In fact it happened to me when I built my new workstation, a few weeks in it just shutoff and was dead, turned out faulty psu.
In a very rare case it can be a cpu (happened to me long time ago) but its super rare that cpu fails.
According to the Dell Knowledge Base, the flash code does appear to be a memory error. I’d try removing all the memory, except for one stick (unless it has to be in pairs) and try powering it back on.
I don’t see any writing on the MB and the on-line manual doesn’t say anything. I do have 2 lights. The power and one on the motherboard, so if the power kicked it, would it have any lights. I know older MB’s had batteries on the MB.
You could have seemingly normal power with a bad PSU but when you try to boot it is either non responsive or can start to boot till there is a load it cant handle then crap out. I would start by looking at the PSU first which can give false positives on other errors.
DELL is coming out, so I’ll let them worry about it. Providing the parts are in, they overnight them to the repair guy and the repair guy calls me when he is on his way.
Okay, it wasn’t the motherboard, it was one stick of RAM. The tech swapped, and swapped RAM, and decided it was the MB. He swapped the MB and it still wouldn’t boot. He did suspect one stick, so after the MB replacement he took it out and it booted. Well, I got a new MB out of it. I have to limp around with 96 GB 
Hope you can get that stick of ram RMA’d under warranty.
Yes, the person I purchased it from told me to send the bad one back and he’ll send me a new on.