Question How to troubleshoot MB that turn on and very quickly turn itself off. No Beeps (H87 - Custom Alienware X51 r2).

[hBarcellos]

Recently I bought an used Alienware X51 r52 barebones (MB, Cooler, PSU) that was supposedly working perfectly.
I then bought an i7 4770 (non-k) which was also supposedly working.
I had a pair of Corsair DDR3 (2x8gb) and, after installing everything, I tried to boot it.
Quick LED flash and all fans spin with an almost immediate power off.
Removed all RAM, wireless card and pretty much everything besides the CPU: Same behavior.
Removed the CPU, MB turns on, still no beeps, but it was kept on (leds and FANs)
Tried to triple check the CPU PINs, to check for something bend, nothing apparent.
Tried to clear CMOS and remove the CRC32 battery. Same behavior.
Tried to measure with a multimeter the CPU (4 pins) cable, coming from the PSU. Voltage seems ok.

At this point, I just need to find a reliable way (I dont have access to another 1150 MB, neither to another 1150 cpu) to try to find out which one is really defective.
For me is way easier to get my money back from the Alienware X51. CPU guys is angry saying that I was the one who ruined his cpu, as, the last time he used it, it was (supposedly) working fine.

Any ideas of what can I try?

PS THis seems to be the motherboard.

 

[Ralston18]

Immediate shutdown.

Possibly a CPU thermal shutdown.

How did you apply the thermal paste and what thermal paste did you use?

Do you have any documentation:

https://www.dell.com/support/home/en-us/product-support/product/alienware-x51/docs

Do verify that I correctly matched your motherboard.

 

[hBarcellos]

Well, just to test it, I tried without thermal paste.
I know it's wrong, but the die was touching the cooler, the CPU fan connector was connected and everything was extremely cold. I highly doubt that the CPU die could reach >90c degrees instantaneously, without thermal paste and, of course, there's not a sensor detecting thermal paste.
About matching, I suppose you're talking about the CPU (as thermal paste) does not need to match with anything! Well, anyway, of course, it's a LGA 1150 Haswell Motherboard matched with an i7 4770 (non-k). The same processor it originally came with.

 

[FarmingTNT]

Recently I bought an used Alienware X51 r52 barebones (MB, Cooler, PSU) that was supposedly working perfectly.
I then bought an i7 4770 (non-k) which was also supposedly working.
I had a pair of Corsair DDR3 (2x8gb) and, after installing everything, I tried to boot it.
Quick LED flash and all fans spin with an almost immediate power off.
Removed all RAM, wireless card and pretty much everything besides the CPU: Same behavior.
Removed the CPU, MB turns on, still no beeps, but it was kept on (leds and FANs)
Tried to triple check the CPU PINs, to check for something bend, nothing apparent.
Tried to clear CMOS and remove the CRC32 battery. Same behavior.
Tried to measure with a multimeter the CPU (4 pins) cable, coming from the PSU. Voltage seems ok.

At this point, I just need to find a reliable way (I dont have access to another 1150 MB, neither to another 1150 cpu) to try to find out which one is really defective.
For me is way easier to get my money back from the Alienware X51. CPU guys is angry saying that I was the one who ruined his cpu, as, the last time he used it, it was (supposedly) working fine.

Any ideas of what can I try?

PS THis seems to be the motherboard.

I've had a problem before where after a few mins (so not instant like you), my whole pc would shut off. It was because my cpu overheated. My fan was broken and required replacing, two of the pins were broken so it just dangled, not making contact with the cpu. Check if the fan is defective? It didn't sound like you considered that a possibility so I guess check that.

 

[hBarcellos]

Well, another thing that amazes me is: why there are no beeps! There seems to be a small speaker directly attached to the board (at the picture, top right of the cpu socket).
Even when turning it on without CPU, no beeps.

 

[FarmingTNT]

Well, another thing that amazes me is: why there are no beeps! There seems to be a small speaker directly attached to the board (at the picture, top right of the cpu socket).
Even when turning it on without CPU, no beeps.

huh weird. Last thing I can recommend is checking other posts on this problem, or maybe find a video online on this MB and see if it beeps? Ngl I find it pretty weird