Take a guess on which part is bad.

[Eelectricity]

Replaced the MB and the GPU both are new. The RAM is new. The PSU was an open box.

So the choices of which part is bad are RAM, PSU, MB, CPU or GPU.

As I said MB and GPU have been replaced but not the PSU or RAM yet.

The symptoms are CPU fan spins up, GPU fan spins up, PSU fan spins up, chassis fan spins up, MB green lights. But no beeps from speaker.
(also tried 2 speakers).

"No signal" is displayed on monitor and monitor tested fine from laptop.

Oh, I have updated the BIOS and reset the CMOS.

 

[PliotronX]

What type of CPU and board is it? If it's a CPU with an integrated GPU, try taking the graphics card out altogether. Unhook everything but the CPU fan, even any HDD or optical drive. Leave just the keyboard and monitor plugged into the mobo (if applicable). This would eliminate a lot of potential variables.

 

[Eelectricity]

No it's not an APU. Have tried all combinations of things plugged in or not.

 

[PliotronX]

Try running only one stick of RAM, perhaps in a different slot if there is only one. Really tough to say without a beep code. I'd say 70/30% PSU/mobo.

 

[LTC8K6]

PSU would be my pick.

Make sure the CPU power connector is plugged in.

 

[Eelectricity]

Tried with 1 stick of RAM. And tried both sticks and in different slots.
Just for clarity the first MB was new and the replacement is new. I am ruling out the MB.

 

[Eelectricity]

CPU pwr connector was plugged in. I think the PSU is the problem.

 

[Ketchup]

Tell us what all these parts are (especially the power supply), they we can make a more educated guess.

 

[Eelectricity]

Tell us what all these parts are (especially the power supply), they we can make a more educated guess.

The parts are all well known and considered reliable from well known and reliable sources. I don't want to muddy the waters with brands as I see that could turn into the a trash-the-vendor fest.

I measured all voltages from the PSU with the system powered on and probing the back end of the connectors. All looked good but that's only part of the story with a PSU.

I doubt the CPU is at fault so the only things left to exchange are the PSU and RAM.

 

[Ketchup]

Good luck then. Some parts vary quite a bit in quality, depending on the manufacturer. I am not sure what you are coming to a forum for help if you refuse to provide information, but that, of course, is your choice.

 

[Charmonium]

A mistake I recently made was forgetting to plug in the additional PCI-E power connects to the HD7950 card. It requires 2 6-pin connectors. I knew that since I had removed the cards from the same bench on a previous m/b just days before but I forgot to plug them in on the new build until I got the same dead screen.

If that's not the problem, I'd check the output of the psu and compare that to what's required. There are a variety of psu calculators out there. You can try this one
http://powersupplycalculator.net/

 

[Eelectricity]

A mistake I recently made was forgetting to plug in the additional PCI-E power connects to the HD7950 card. It requires 2 6-pin connectors. I knew that since I had removed the cards from the same bench on a previous m/b just days before but I forgot to plug them in on the new build until I got the same dead screen.

If that's not the problem, I'd check the output of the psu and compare that to what's required. There are a variety of psu calculators out there. You can try this one
http://powersupplycalculator.net/

The GPU was connected properly. The instructions are in large print on the GPU box.
The wattage rating was fine, well over the wattage draw of the parts.

 

[Smoove910]

Hmmm, you've made it extremely hard for us to help trouble-shoot. I'd say try a different PCI-e slot, but of course you refuse to give specs so we know what the heck we are dealing with.

Imagine taking your car to the mechanic because is doesn't run right... but you won't tell him what motor you have because :

The parts are all well known and considered reliable from well known and reliable sources. I don't want to muddy the waters with brands as I see that could turn into the a trash-the-vendor fest.

Good luck!

 

[denis280]

The parts are all well known and considered reliable from well known and reliable sources. I don't want to muddy the waters with brands as I see that could turn into the a trash-the-vendor fest.

I think it's this or that,or it could be the other thing??? spec.would be perfect

 

[daveybrat]

The parts are all well known and considered reliable from well known and reliable sources. I don't want to muddy the waters with brands as I see that could turn into the a trash-the-vendor fest.

I measured all voltages from the PSU with the system powered on and probing the back end of the connectors. All looked good but that's only part of the story with a PSU.

I doubt the CPU is at fault so the only things left to exchange are the PSU and RAM.

How are we supposed to help you if you won't help us?? We aren't magicians. We need to know what you are working with to help you.

Without more information this thread is useless.

 

[VirtualLarry]

Without more information this thread is useless.

Agreed. I have requested that the thread be locked, due to OP refusing to divulge hardware specs.

 

[PliotronX]

Just one more item to add: yes testing voltages tells almost jack and squat from my experience. I lost a bet about a bad PSU in an old Dell Precision that would not even respond to the power switch because all rails looked fine and it would power anything through molex with the ATX header shorted to power on. New power supply powered it right up and functioned like new.

 

[crashtech]

Is this equipment being tested outside of the case laying on a bench?
Does the CPU have integrated graphics?
How does one know the BIOS is updated successfully during a no-boot condition?
Is there another known good PC of similar specs available?

Without known-good spare parts or another machine to use for testing, you might as well flip a coin.

 

[PliotronX]

Is this equipment being tested outside of the case laying on a bench?
Does the CPU have integrated graphics?
How does one know the BIOS is updated successfully during a no-boot condition?
Is there another known good PC of similar specs available?

Without known-good spare parts or another machine to use for testing, you might as well flip a coin.

+1 a Magic 8-ball may be more accurate however.

 

[Eelectricity]

Just one more item to add: yes testing voltages tells almost jack and squat from my experience. I lost a bet about a bad PSU in an old Dell Precision that would not even respond to the power switch because all rails looked fine and it would power anything through molex with the ATX header shorted to power on. New power supply powered it right up and functioned like new.

Yep, new PSU is on the way.

 

[Eelectricity]

Is this equipment being tested outside of the case laying on a bench?

Both inside and out.

How does one know the BIOS is updated successfully during a no-boot condition?

Some MBs let you update BIOS with no CPU,RAM,GPU.

Is there another known good PC of similar specs available?

No. I wish.

Without known-good spare parts or another machine to use for testing, you might as well flip a coin.

Or even submit a poll!

 

[Eelectricity]

+1 a Magic 8-ball may be more accurate however.

Or a poll on anandtech!

 

[crashtech]

Some MBs let you update BIOS with no CPU,RAM,GPU.

That's not news, but what would be unusual is first for this to be attempted with a suspected bad PSU, second to have it succeed, then third to deem the results be trustworthy. Flashing the BIOS on a non-functional system is kind of a last resort, not a first step, imo, unless there is a known specific problem that is being addressed.

How about beep codes? Is there a PC speaker?

 

[denis280]

The PSU was an open box.

Swap it

 

[Dude111]

Replaced the MB and the GPU both are new. The RAM is new. The PSU was an open box.

Im so sorry your having problems and I do hope you can get them corrected straight away