It comes down to these possibilities: Bad motherboard, bad RAM, voltage on RAM not compatible, short in the tower's power button switch, weak PSU, non compatible PSU (has to be 12V?)
This is a long post containing three hours of trouble shooting condensed into these paragraphs. I hope I can be able to help anyone else out with similar problems. Please read it all before giving a suggestion because I have tried many suggestions already.
I have tried the suggested problems thread and nothing there worked. Here's what I think. I have a Coolmax 480W power supply thats about 5 years old. I think it's too weak to even turn on my system but the only things connected to it are my motherboard with the Intel Core i7 920 processor in it along with the stock fan, and my HD 4870 1GB GDDR5 PCI x16 graphics card. The graphics card came with two, 6 to 4 pin adapters. This is good because my old PSU doesn't have any 6 pin power on it. I hook the two six pins into the graphics card, each pin has two, 4 pin adapters; that makes four, 4 pin adapters. I plug all four up to my power supply, plug in my 20+4 pin connector to the motherboard and thats it, nothing else's power is plugged in. I push the power button on my tower and it doesn't turn on.
Is the PSU too weak to even power it on? I have unplugged EVERYTHING else in an attempt to get it to power on. This is a complete custom build. The case has a wire runs from the power button to the inside of the case. From there, I connect the pin to the motherboard according to a chart. The motherboard manual says "Power BTN" goes in pin 4 we will say for example. But the wire has two holes, not one. Other wires are easy to attach. Another example, motherboard says "Power LED +" goes in pin 1, good, it only takes up one pin so i stick it in. "Power LED -" goes in pin 2, good, it also only takes up one pin. Next, "Power BTN" goes in pin 3, but the actual connector takes up two pins. It fits, but on two pins, and I think one is a ground. I have tried plugging that "Power BTN" in the orange connector on the motherboard in any way possible and still no luck.
My motherboard supports triple channel RAM up to 2000mhz (OC) per stick. I purchased 1866mhz ram (not OC). It says it supports 1866 mhz (OC). Does this mean my natural speed of 1866mhz is not supported, only slower speeds that CAN be pushed to 1866mhz?
Also, I have tried all three sticks of RAM one by one in every slot trying to power on my computer. How do I tell of the voltage is too high? I mean, if my RAM is not compatible, will my computer not start AT ALL? Can I turn on my computer with absolutely no RAM? I have tried and even with no RAM it still does not work.
Here's the weird thing. I tried to power it up for an hour last night, it wouldn't so I hit the net for some help. Looked back behind me after about 20 minutes and the motherboard was on. How do I know? It has a little debug display that shows numbers on it that glows red. It's a simple two-digit display. I wish it showed a number but it didn't, it just showed sort of a half of a "0". Before I touched anything, I hit the power button to try to turn it off, it would not respond. I hit it a few more times and nothing. I then unplugged the power, then plugged it back in and hit the power button. Nothing happened.
I'm getting a brand new 750W modular power supply in five days (yay for ordering Tuesday nights; 3 day shipping becomes 6 days for Newegg). Maybe that will help. Five days is kind of long to wait. This whole experience is turning out to be a nightmare. Tigerdirect charged me twice on accident for my i7 processor causing my bank account to reach -$178.
Hi-Res pictures below of my system that won't power on.
Your first picture above shows an obvious problem. The 8-pin CPU power connector is not plugged in. The CPU power connector is in the upper left corner of the picture near the CPU socket and is labeled "ATX12V1". The system doesn't have a chance of booting without power to the CPU. That's #2 on the checklist and the most common mistake. I don't know how you missed that since you said you went through the checklist.
The other thing is that your POS CoolMax PSU doesn't have a chance of powering that system. I wouldn't even try to get it running until you get your new PSU.
I'm also not convinced your case power connector is plugged in correctly. You need to double check that in the owners manual. The plugs usually are turned the other way. It's hard to explain, but it should go where the X's are below:
I hook the two six pins into the graphics card, each pin has two, 4 pin adapters; that makes four, 4 pin adapters. I plug all four up to my power supply, plug in my 20+4 pin connector to the motherboard and thats it, nothing else's power is plugged in.
^ That's it? If that's the case, then you forgot the 4/8 pin CPU power. You need a 4/8 pin adapter from the PSU to plug in next to the CPU on the board.
It's #2 on the troubleshooting stickey.
edit: Look at the quickness of shortstuff....beat me to it.
Oh dear God thank you both so much. My PSU is so old the cord lengh will barely reach. I'll try it right now. I thought I had the choice of doing the 4/8 pin OR the 20+4 pin connector. Thanks so much now I understand. I'll post back if it worked.
Ok. I plugged in the CPU 4 pin connector, then the motherboard 20 pin connector, but that didn't work for me; even with the case power connectors connected according to the manual. And the case power connectors, I do have them the wrong way in the picture. But for two hours beforehand, I had them in the right way according to the manual. I was just trying any possible placement to see if I could get power.
Well if the CoolMax won't power it, then I will have to wait for my new PSU. The CoolMax has a four pin connector, but it was tied with the 20 pin motherboard connector. I cut the sleeve and moved the 4 pin connector over and plugged it into the CPU power connector, it would only go to the far left four slots (farthest away from CPU). I then plugged in the 20 pin mobo connector and no power. My old Dell 350W PSU has a 4 pin connector for the CPU (four right holes closest to CPU) that go into the other holes the CoolMax couldn't fit. That has no chance of even powering it on.
BTW, my RAM sticks say 1.65V a piece on them if that helps with anything.
I don't know if this is dangerous or what but I took one PSU and plugged it into the CPU power connector, then I took the other PSU and plugged up the MOBO 20 pin and my graphics card. Still no luck. I doubt that it would even boot though with two PSU's connected. Seems dangerous.
You can't rob 4 pins from the 24-pin connector. You need all 24-pins AND the CPU power connector. If the PSU doesn't have 24-pins for the motherboard and at least a 4-pin for the CPU it will not work. Like I said, I wouldn't even try to power that system with that POS unless you like indoor fireworks.