Topic: All looks good, but monitor doesn't light up

[VANGUARD]

I assembled a computer for my supervisor here at work. The following occurred:


Power supply fan turns on
CPU/processor fan turns on
Mainboard light turns on (green color)
DVD drive lights up, can be opened and closed
Keyboard lights up (hitting numlock on and off)

However, the monitor doesn't turn on. I had tried two different monitors, and both the onboard and a separate graphic card.

Any ideas as to what is up?

[Foil]

First, I'm assuming the monitor is plugged in and turned on, and that what you're describing is the monitor staying in 'sleep' mode (no image).

Something to look at:

Is the hard drive active (is the machine booting up?)

Some things to try:

Different monitor inputs (e.g. switch the monitor between digital/analog)

Try a different machine with the monitor (this will tell you if the monitor is the problem or not)

[VANGUARD]

right, both I guess in sleep mode, if that's what one calls it. they're both blank in other words. The first time I powered up the PC, I saw the "asus" splash screen". now I don't see it on that or on another monitor. I'll ty analog/digital, if it has the digital input.

update: tried different monitors, no change. unplugged harddrive, no change. tried analog and digital, no change.

As soon as we get this working, he is going to install linux on it, and not just any, he gave me the ok for me to choose one, and I know what I will be using. hint, check out my avatar

[-<WillyP>-]

Two things, a power supply tester and a post tester.

Both are very cheap tools, the power supply tester will tell you either voltages or a go/ no-go.  The post (Power On Self Test) tester has a two digit readout plus leds, and you look the code up in the book that comes with it.

I think the power supply died.  Do you have another one to try?

[VANGUARD]

Most here are 20 pin, we need a 24 pin. I think my supervisor has one; maybe two, but it's one that's a pretty important one to run. I think it's the server, something like that.

[TechPro]

I'm going to ask what may sound like a silly question ... but there is a reason.

The hard drive, what kind is it?  If it uses a ribbon cable, is the cable connected to the motherboard correctly, and not reversed?   Same question for the DVD drive.

If the ribbon cable is attached backwards, it can cause the symptoms you've described.  I believe a ground line gets connected to a data line and that effectively holds things "down" and unable to process the POST which also results in no video and no startup.

[VANGUARD]

This has that SATA hookup. I don't think that can get reversed. can the ribbon, think that's IDE, get reversed? or am I missing what you're getting to?

update: just checked with a working power supply, but no change when placed in this pc.
another thing i have been noticing. There aren't any beeps like you'd normally hear when you boot up a pc

[TechPro]

Depending on the connector design, IDE cables may or may not be able to be reversed at the motherboard.  The socket at DVD drive or hard drive is usually keyed so that cannot happen at the drive.  The motherboard is a different story.  I've seen the IDE cable get reversed at the motherboard, on multiple brands.  The effect is the lights of the system come on, it appears to be powering up, but nothing happens.

If there are no IDE style cables being used in the system, then this would not apply to it.

[VANGUARD]

how about connecting the reset button, hd led, power led, power switch, etc. if reversed, can that cause something bad? i think I tried reversing the power switch. but nothing changed.
i don't get it. monitor and no beeps is all i see that seems wrong, and so far, no matter what i do, nothing seems to be working.

[TechPro]

How about the memory modules?  Have you tried different modules?

Beyond that, I'm about out of ideas unless there is a problem with the power cables attached to the motherboard, other connectors, the processor (and/or the way it's installed), or the power supply (set to the correct voltage?).

[VANGUARD]

I don't know what else it can be. I do appreciate your help guys. I wish I was more of an expert in this field.

[VANGUARD]

I apologize. I didn't have the external speakers hooked up, so I never heard any beeps. oops.
After I plugged it in, it beeps three times, repeatedly.

Also, if this helps any, I turned on the monitor. It showed the asus logo, then "No Signal."
As soon as I powered up the PC, it disappeared and went in sleep mode.

[VANGUARD]

according to another forum, it may be a bad base 64K memory.

http://www.bleepingcomputer.com/forums/topic320435.html


it sounds exactly like this computer is doing. three rapid beeps, one after another, and monitor not turning on

[-<WillyP>-]

You should google the manufacture of your mobo.  I am not sure if the beep code is standard, or if it varies by manufacture.  Find out what your beep code is.

[VANGUARD]

I checked, and it does look like the base64k memory is bad.
My guess is that the memory card is the wrong type, or size. Let me explain.
In the mainboard manual, they show some models and types it supports, basically they show a list of DDR2 667 and DDR2 800. The one that my supervisor got is some 400 model, maybe DDR2, not sure right now. but it's no 667 or 800.