Power on, black display, no BIOS beeps?

My computer gets power, but nothing comes up on the display, and no BIOS error beeps are heard. Here's my system information and the whole story.

My system:

PSU: Antec earthwatts 380
MoBo: Asrock 4coredual-VSTA
CPU: Intel Core 2 Duo 4500
GPU: Ati 4830 hd
HDD: western digital 160Gb sata
RAM: 2x Kingston 533Mhz DDR2

My GPU, the 4830, has been unstable since I bought it about a month ago. The GPU often has to reboot itself, and it gives an error message about that in XP. Sometimes it goes to an infinite loop, and XP gives the blue screen of death.

I thought this is probably because asrock doesn't have a PCI-e 2.0 slot. However, as I understand the 4830 should still work it's PCI-e slots, just without using all possible bandwith.

One day, as I was backing up my entire hard drive to a sata drive an external eSata-hdd case, the computer just went off like someone pulled the plug.

When I turned it on, I could hear that the fans and drives went on, but there were no beeps and the display was black (well, not black, but with the LCD-displays default message that it is receiving no signal).

So, I took out my old 8400 GS graphics card and plugged it in instead of the 4830. The exact same thing happened. The motherboard has no GPU of it's own.

I figured that maybe the PCI-e slot on my mobo had somehow been broken, so I went off to buy a brand new mobo, an Asus P5Q-E. However, the exact same thing happened with my new mobo. And with both cards. The new mobo has no GPU of it's own either. Power seems to go on, fans working, cd and hard disk get power, but nothing on the display and no error beeps.

So, I started debugging the system by taking everything off. When I take off everything except the CPU and MOBO, it gives me the error beep for no RAM detected. But when I insert either or both of my RAM sticks, it goes back to no message.

Shouldn't it beep for no graphics card found, or something else, next?

As I understand from googling around, the 533Mhz DDRII shouldn't be a problem, even though Asus P5Q-E specs only says that it supports 1066/800/667Mhz.

However, could it be a problem that the EarthWatts only has a 4-pin ATX power connector for the mobo instead of an 8-pin, that is required according to the manual? This was my mistake, didn't understand to check for it when buying the Asus motherboard. :(

(Also, IF you think this is a problem, does it seem like my symptoms are because of this or something else? Why didn't the old mobo not work, even though the 4-pin was for sure correct for the Asrock mobo?)

So... Is the problem with my PSU, CPU or RAM? Or, how to debug further? I wish I had different DDRII sticks to test with, but unfortunately not. No spare PSU's or CPU's either. I guess I can exclude the possibility of two broken mobos?

Or am I missing something else entirely here?

(I'd hate to take it to maintenance, because I'd probably rather buy new components than pay for repairs and wait for weeks. But what to buy??)
3 answers Last reply
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  1. i'd say the 4-pin issue is defiantly your problem.

    the asrock might not have had as much crap on-board as the asus does (leds, fan and temp connections, etc.) and thats why it only required a 4-pin (thats just peculation on my part though).
  2. I think you've already answered your own question:

    "But when I insert either or both of my RAM sticks, it goes back to no message."

    Sounds like a RAM problem. Most motherboards will run fine with just the 4-pin CPU power connector. Your troubleshooting seems to point to the RAM. Here's a checklist to do further troubleshooting:


    Thanks for the tip, shortstuff_m! I went and bought new RAM, and my machine is up and running!

    I wonder what happened to those lifetime guaranteed Kingston RAMs...
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