Freezing at first boot - help !

All,
I have a pc with WinXP, a GeForce 6600 GT and SB Live soundcard.

The pc has always worked, but since a week I'm experiencing a weird problem, after 5-10 minutes of the first boot - when the machine is still 'cold', it freezes, and I have to press the reset button for a reboot.

After this first boot (or more, depends on how quickly the pc reaches a good temperature) no freezes occurr amymore.

It happens basically when the pc stays off for some hours, so that all the components are cold.

In fact after google research I've found that it could be a temperature problem with the Nvidia card. So I've installed the newest drivers for the 6600GT, but sadly it did not help.

According with some user hints on the nvidia forum, I've also changed the "PCIE" frequency from Auto to 110 Mhz but still no joy.

Another hint says that AGP Fastwrites must be disabled, and so the 'Sideband Adressing' but I can't find it in my nvidia control panel.

If the pc is still in a "unstable" modus, if freezes also during browsing the Bios !

Last thing, it happens also without internet connection. So it is not a new internet worm - at least, so I guess. Also, it happens whatever program I run - even in idle.

This problem is driving me quite mad, so if someone of you has experienced a similar issue and solved it, please let me know.

Regards,
Sergio.

Just double check you've got everything seated in its relevant slots tightly...to be honest this sounds like a dodgey connection somewhere and nothing more ( particularly sensitive to cold starts) ....this includes your IDE connectors for hardisks, and your ram slots etc. or whatever else you've got set-up.

If it freezes even in the BIOS, then it likely is hardware related rather than software.

Like Hujiklo suggested, make sure that all your components are seated properly. Actually, you may want to take out your memory, PCI cards, etc. and make sure that the connectors are clean and that there is no dust or gunk stuck in the slots. when the parts get warm they expand a little, or if you have a bad connection it may work poorly when cold but 'magically' start working when it warms up.

I'm sure you can enable/dosable sideband addressing and fast writes and such in the BIOS. Seems like a strange problem to have. I leave my PC off for days sometimes and come back to it and it's fine.

It could be a crack in the Motherboard. When the board gets to a certain temperature, it expands causing the crack to cause problems. But, if you say once it gets going it's fine, i dunno. Could be a number of issues...

I've had an issue since I upgraded my PC months ago where it will have problems detecting the drives on boot and just sit there, but when I power it off and turn it back on it will then detect them. After that it works fine. I'm pretty sure it's one of the drives causing this, or the fact that I have five drives in there. Eventually I'll take a few out and replace them with a 1tb drive.

Thanks all for the kind replies.

I've opened the chassis and noted that the video card chip has a copper cooler that was quite detached from the chip itself and from other 4 chips, which are refrigerated by the same cooler too.

So I've repristinated the thermal compound film with new ones and right now, after 30 minutes from the first boot, it is still working :)

Cheers,
Sergio.