P7P55D-EPRO no beep code and VGA POST fail

aldocfo

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Bench testing new MOBO with chassis speaker + new TX650 PSU (voltages check OK) + new i5-655 with Akasa HCU + single 2 Gb DIMM + ATI HD5770 GPU with VGA attached. All fans function OK. MOBO powers up and proceeds with testing -> RAM POST LED and CPU POST LEDs flash as expected. MOBO VGA POST LED stays on indicating GPU failure(presumably?). Repeat exercise after removing GPU - and reach the same visual VGA failure cue (as would be expected). No beep codes on either occasion. Why? Presumably the MOBO is faulty? Help would be appreciated.
 

GoldenI

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If the Mobo was faulty then I highly doubt that it would even reach POST. The fact that it even turns on means that the motherboard is working properly and the CPU is working properly. It isn't the CPU, either, because if that were the case then the fans would not be working and the computer would not be lighting up at all. Without the CPU, NOTHING and I repeat ABSOLUTELY NOTHING functions. Essentially it's like a person in a vegetative state due to brain damage. Anybody who tells you any different is a complete idiot.

It is most-likely a failure in the GPU department.
 

suat

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Reseat VGA card and connect its power cable securely.

Also make sure you have installed RAM stick in A1 or B1 slot ( blue slots ). Single RAM in A2 or B2 does not work.

Once your system is up and running, BIOS update may be in order.
 

aldocfo

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Thanks GoldenI, I will focus on the the GPU, but I'm curious/suspicious regarding lack of POST audio signals.
 

aldocfo

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Thanks Suat, Tried RAM stick in both both slots (A1/B1) and both pass LED light test point.

Tried GPU in both PCIE-x16 slots and both produce same Mobo VGA LED failure point. Card is seated properly and clamped, 6-pin PSU line firmly attached to GPU. GPU fan is running. When would you expect the POST audio warning to occur if the BIOS has effectively halted part way through?
 

GoldenI

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Perhaps the motherboard speaker became unplugged.
 

suat

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If VGA LED light is shining red, then you do not get any warning beep. The warning is the RED light shining continuously.

I know that because I had a similar problem about six months ago. My problem was, my computer could not boot up due to VGA card, but only once out of about ten cold bootups. No beeps sounded. The computer remained as if it was not powered up.

When that happened, I shut the computer down with the case power button and turned it on again. Then it worked fine as if nothing wrong happened.

I did not do anything to solve the problem as I could not think of anything to do except that I continued to update my BIOS. I updated my BIOS four times. Then after BIOS v.1702, my problem stopped recurring. I do not know if it is the BIOS update that removed the annoyance or something else happened out of my knowledge and control. My motherboard is P7P55D with Intel i7-860 and 8 GB DDR3-1333.
 

aldocfo

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Thanks Suat, very useful experience. The relationship between Asus Mobo warning light sequence and when POST audio warnings will first be heard is pretty fundamental. It would have been helpful if Asus made reference to this fact of life in their Mobo manual!

For now I can't reach the starting point for updating the BIOS!
 

suat

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What I can suggest is, take the motherboard battery out for ten minutes and re-install it and see if this helps.

By the way, I also have Sapphire Radeon HD5770. This card was difficult to install. I had to use much force to seat it and I used two screws to fix it in place although my PC case has clips to hold PCI and PCIe cards in place.

For info, in my system POST LEDs shine: CPU (1 sec), RAM (1 sec), CPU (1 sec), RAM (10 sec), VGA (3 sec), then a single beep and POST screen appears. The time measurements are approx. I have a time lapse of 15-16 secs before the beep sound.
 

Korrupter

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I am having a kind of a similar problem. My PC specs are i5 750, P7P55D, 4GB Corsair Doms.
Computer boots up for the first time when VGA (9600GT) is in PCI-E x16 slot but when I restart the computer. The VGA LED is shining red & no post then I changed my GPU from PCI-E x16 slot to PCI-E x4 slot. It starts working again & no problems on restart. Change the GPU back to the x16 slot. It will work but on restart, same problem again.

Any help would be appreciated.
 

aldocfo

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Korrupter et al,

Thanks everyone - tried the suggestions, including a replacement GPU - all to no avail. Finally returned the MOBO to my supplier who, following checks, agreed a replacement. Needless to say this new P7P55D-EPRO passes POST without hesitation! Windows 7-64 now working well. Your help much appreciated.