A7N8X-X won't boot--too little power?

[Jerry Slaff]

Just got a A7N8X-X motherboard, along with a Athlon 2600 and 512MB
PC2700 Kingston RAM. System is not even getting to boot stage--no beeps,
no jingles, no voice. System automatically shuts down in about 5
seconds. This is out of the case, with just a video card
connected--nothing else. I've also tried it with no RAM, and no CPU,
just to get to the BIOS. Nothing.

My power supply is on the low side--300W max. (I've ordered a new 500W
PSU.) Is that the problem?

Jerry

 

[Dave Etz]

Just got a A7N8X-X motherboard, along with a Athlon 2600 and 512MB
PC2700 Kingston RAM. System is not even getting to boot stage--no beeps,
no jingles, no voice. System automatically shuts down in about 5
seconds. This is out of the case, with just a video card
connected--nothing else. I've also tried it with no RAM, and no CPU,
just to get to the BIOS. Nothing.

My power supply is on the low side--300W max. (I've ordered a new 500W
PSU.) Is that the problem?

Jerry

Check the fit of the heat sink and fan on the processor. If it thinks its
going to overheat, it will shut down before any damage occurs. If the heat
sink isn't in the proper position, or the fan isn't working, or the fan is
plugged into the wrong connector on the mb, it will not go for love nor
money.

Dave

 

[Canus_Lupis]

Just got a A7N8X-X motherboard, along with a Athlon 2600 and 512MB
PC2700 Kingston RAM. System is not even getting to boot stage--no beeps,
no jingles, no voice. System automatically shuts down in about 5
seconds. This is out of the case, with just a video card
connected--nothing else. I've also tried it with no RAM, and no CPU,
just to get to the BIOS. Nothing.

My power supply is on the low side--300W max. (I've ordered a new 500W
PSU.) Is that the problem?

Jerry

You will get this sometimes if your AGP card is not seated all the way in.

 

[Jerry Slaff]

Thanks for the help. I've even tried it with a PCI video card, and even
WITHOUT the agp card at all, and the same thing happens. I've reseated
the fan on the chip, used arctic silver on it (very carefully), and have
the fan plugged into the correct port on the motherboard.

Since in each instance I get the same result--and this is the second
motherboard--it can only be the PSU (unless they shipped me another bad
motherboard, which I doubt).

The PSU now runs a P3/1000 on an Intel motherboard fine. I've never
experienced any power problems, but I'm thinking that what is labeled as
a 300 watt max PSU really is putting out closer to 250. We'll see this
weekend....

Jerry

 

[Arnie Berger]

Thanks for the help. I've even tried it with a PCI video card, and even
WITHOUT the agp card at all, and the same thing happens. I've reseated
the fan on the chip, used arctic silver on it (very carefully), and have
the fan plugged into the correct port on the motherboard.

Since in each instance I get the same result--and this is the second
motherboard--it can only be the PSU (unless they shipped me another bad
motherboard, which I doubt).

The PSU now runs a P3/1000 on an Intel motherboard fine. I've never
experienced any power problems, but I'm thinking that what is labeled as
a 300 watt max PSU really is putting out closer to 250. We'll see this
weekend....

Jerry

It's time to do a reset and start over. First, I don't think the power
supply is the cause, but it might be. Try this:

1- Remove the MOBO and power supply from case. Set it up on an
insulated tabletop.
2- Remove the processor and check the pins by sighting down each row
from two directions. Look for bent pins. If you find a bent pin,
you've got the culprit. Now the challenge is to straighten it without
breaking it.Good luck here.
3- Reseat the processor, making sure that the pins drop into the
socket smoothly.
4- Attach the heat sink and connect the fan to the proper connector.
Unless the tachometer output of the fan signals that the fan is
rotating at the proper speed, you'll get the same symptom. This also
implies that a bad fan tachometer will also cause a problem.
5- Reconnect the memory simms, the video card, the keyboard and mouse.
You can omit any disk drives at this stage.
6- Turn on the MOBO by shorting together the two pins that would
normally go to the power switch.
7- If you still don't get it starting, look at the fan as the culprit.
If a replacement fan doesn't cure it, then it is either the MOBO, the
processor, or the power supply.

It could ultimately be that one of the voltage rails of the power
supply is insufficient to power the board and processor. The 3.3V rail
is the most likely. Your new supply should verify this. However, my
250 watter got it to at least start-up.

arnie

 

[Ben Pope]

1- Remove the MOBO and power supply from case. Set it up on an
insulated tabletop.
2- Remove the processor and check the pins by sighting down each row
from two directions. Look for bent pins. If you find a bent pin,
you've got the culprit. Now the challenge is to straighten it without
breaking it.Good luck here.
3- Reseat the processor, making sure that the pins drop into the
socket smoothly.
4- Attach the heat sink and connect the fan to the proper connector.

Remebering to do the paste properly and correctly orientate the heatsink -
usually there is an edge that lines up with the raised part of the socket.

Unless the tachometer output of the fan signals that the fan is
rotating at the proper speed, you'll get the same symptom. This also
implies that a bad fan tachometer will also cause a problem.

Or a fan running low RPM - on the normal 'N8X about 1800RPM is lower limit
for it registering a fan.

5- Reconnect the memory simms, the video card, the keyboard and mouse.
You can omit any disk drives at this stage.
6- Turn on the MOBO by shorting together the two pins that would
normally go to the power switch.

On ATX supplies, you only need to make a temporary connection. I think it
basically short pins 23 and 24 (or is that 25? .

7- If you still don't get it starting, look at the fan as the culprit.
If a replacement fan doesn't cure it, then it is either the MOBO, the
processor, or the power supply.

It could ultimately be that one of the voltage rails of the power
supply is insufficient to power the board and processor. The 3.3V rail
is the most likely. Your new supply should verify this. However, my
250 watter got it to at least start-up.

If it's an older supply it won't be expecting the 7A or so current on the
12V rail that the CPU is gonna pull.

Ben

 

[Jerry Slaff]

Remebering to do the paste properly and correctly orientate the heatsink -
usually there is an edge that lines up with the raised part of the socket.

[snip]

Thanks for the ideas. The CPU fan is 3000RPM, and it's seated correctly.
so I don't think that's the case. I'm leaning toward the PSU as the
culprit--we'll see soon enough.

Jerry

 

[Jerry Slaff]

Yep, it was the PSU. I installed a 500W yesterday, and the unit's
working fine.

One question, though. The PSU has two fans. One faces out of the case,
and exhausts. The other is internal to the case, and faces downward to
the motherboard.

Frankly, I closed up the case without checking, but is that an intake
fan? It wouldn't make sense for it to exhaust hot air ONTO the motherboard.

Jerry

Remebering to do the paste properly and correctly orientate the
heatsink -
usually there is an edge that lines up with the raised part of the
socket.

[snip]

Thanks for the ideas. The CPU fan is 3000RPM, and it's seated correctly.
so I don't think that's the case. I'm leaning toward the PSU as the
culprit--we'll see soon enough.

Jerry

--
=====================================
Jerry Slaff
Rockville, MD, USA

Remove .invalid for my real e-mail address

 

[Jeannot]

i had one like that, and i changed the direction to exhaut outside the
units not inside toward the M/B

Yep, it was the PSU. I installed a 500W yesterday, and the unit's
working fine.

One question, though. The PSU has two fans. One faces out of the case,
and exhausts. The other is internal to the case, and faces downward to
the motherboard.

Frankly, I closed up the case without checking, but is that an intake
fan? It wouldn't make sense for it to exhaust hot air ONTO the motherboard.

Jerry

Arnie Berger wrote:

1- Remove the MOBO and power supply from case. Set it up on an
insulated tabletop.
2- Remove the processor and check the pins by sighting down each row
from two directions. Look for bent pins. If you find a bent pin,
you've got the culprit. Now the challenge is to straighten it without
breaking it.Good luck here.
3- Reseat the processor, making sure that the pins drop into the
socket smoothly.
4- Attach the heat sink and connect the fan to the proper connector.



Remebering to do the paste properly and correctly orientate the
heatsink -
usually there is an edge that lines up with the raised part of the
socket.

[snip]

Thanks for the ideas. The CPU fan is 3000RPM, and it's seated correctly.
so I don't think that's the case. I'm leaning toward the PSU as the
culprit--we'll see soon enough.

Jerry

--
=====================================
Jerry Slaff
Rockville, MD, USA

Remove .invalid for my real e-mail address