NF7-M no POST, siren - New System

Just put together a new system:

NF7-M mobo
Athlon XP+2700
256mb Centon PC3200
400W PS (P4/Athlon rated w/atx12v plug)

no add-on cards - PCI or otherwise
1 CD/RW drive - on IDE 2
1 DVD drive - on IDE 2
1 Hdd - on IDE 1
1 floppy

generic mouse/keyboard/display

When I turn on the PS, a red LED next to the FPIO1 connector lights up.
When I push the PWR button, a green LED in the same position also lights up.
Next the monitor may/may not come on, followed by a beep, a pause, then a
siren.
This continues until you turn off the PS.
So far the drives spool & the POST screen comes up, then almost immediately
the siren begins and everything dies.

I've tried resetting the CMOS to no good result, needles to say I am stuck.

 

That indicates either the heatsink is not mounted properly, causing the
CPU to get too hot and shut the system down with the BIOS beep code you
have, or the heatsink fan is not plugged into the header on the MB for
the CPU fan, or the tach signal from the heatsink fan is "dirty", and
not being seen by the BIOS.
Quite often, the heatsink is mounted 180° turned around, and is not
contacting the CPU properly.

 

That makes sense, it seems to get farther into the boot process if it's been
sitting cold for a while. Could it hurt/help to use some type of heatsink
compound? How do you tell what orientation to put the heatsink fan?

 

Is it the retail heatsink you're using, and does it have the thermal pad
on it? If so, did you remove the blue tape before installing the
heatsink?

Usually, the bottom of the heatsink has a step in it, and this is
matched up to the step on the CPU socket. That's the best way to tell
if it's on correctly.

 

It's not a/the retail heatsink, bought it at the local mom&pop pc store. It
did have a small rectangle on the bottom of it, may have been the thermal
pad. There was a large Remove Before Flight sticker that I peeled off, the
squareish spot was under the sticker. I won't be able to check it till I
get home.

 

Then, it's very probable the heatsink is on "backwards". Remove the
heatsink and clean the thermal pad off it and the CPU die. You may have
to scrape the bottom of the heatsink to get it all off. Be careful not
to scratch it. Clean the heatsink and CPU die with acetone, or
isopropyl alcohol. If you use acetone, final clean with isopropyl
alcohol, then apply a *thin* layer of heatsink compound. If you don't
have any, you can pick up a small tube at your local Radio Shack store.

 

Thank you for the help. I'll let you know tomorrow how it goes.

 

You're welcome, and I'll be watching for an update.

 

It does sound like he didn't use any pad or thermal compound. I have never
seen a heatsink that had a thermal pad under a protective cover. If there
wasn't any thermal compound or pad that sure would make it overheat pretty
quick and even quicker if the heatsink wasn't touching the core at all.

 

Good point. I imagined a thermal pad under the "remove before use"
plastic, but didn't think it may not have had one at all. If that's the
case, it would explain the high temp, as well as make things easier for
him to reinstall, since there won't be a thermal pad to scrape off.
Thanks!

 

It took me maybe two minutes to get into the case, take off the heatsink,
clean it up, put it back on the obviously correct way (now that I know what
to look for I feel like an idiot) and turn it back on.... Yahtzee, it
worked like it was made that way.

Thanks alot, Icee!

 

Thanks for the update, Proofs. Glad it was as simple as reinstalling
the heatsink, and you're welcome!