Windows (bootup) freeze at low chassis temps - solutions?

[Orclas]

My T400 (6475-W32) has since I bought it used a year ago displayed a very strange problem: it freezes at boot when chassis temps are low.

At room temps (20C/70F+) it's all fine, around 15C/60F it's into the risk zone, below that a freeze is certain and at temps below say 10C/50F it may at times freeze at more than one boot attempt. Freezes usually occur at windows login screen or short after, but at times also before that. Once it has run for a few minutes, it's all fine (presumably since components have heated up a tad).

I've identified the culprit being the WiFi card (Intel 5300AGN) and it's only by physically removing the card that the problem goes away (HW radio on/off and/or disable wifi in Windows does not help). I sourced a new one off ebay, but the problem unfortunately persists and although more of a nuisance than a problem, I would prefer to get it fixed.

Next suspect is ofc the motherboard itself, but any thoughts and comments are most welcome, including conclusions about it indeed being the motherboard.

[jayton4]

My T400 (6475-W32) has since I bought it used a year ago displayed a very strange problem: it freezes at boot when chassis temps are low.

At room temps (20C/70F+) it's all fine, around 15C/60F it's into the risk zone, below that a freeze is certain and at temps below say 10C/50F it may at times freeze at more than one boot attempt. Freezes usually occur at windows login screen or short after, but at times also before that. Once it has run for a few minutes, it's all fine (presumably since components have heated up a tad).

I've identified the culprit being the WiFi card (Intel 5300AGN) and it's only by physically removing the card that the problem goes away (HW radio on/off and/or disable wifi in Windows does not help). I sourced a new one off ebay, but the problem unfortunately persists and although more of a nuisance than a problem, I would prefer to get it fixed.

Next suspect is ofc the motherboard itself, but any thoughts and comments are most welcome, including conclusions about it indeed being the motherboard.

My guess would be the hard drive. Try booting to a live cd or flash drive of ubuntu to see if it still locks up then.

[Orclas]

My guess would be the hard drive. Try booting to a live cd or flash drive of ubuntu to see if it still locks up then.

In that case there's an easier solution, namely plopping the original HDD back in (I immediately supplied it with an SSD after purchase).

[Orclas]

No luck, using the original HDD makes no difference (but does remind me of the greatness of SSD). I also just realized that I forgot to mention in my OP that I have also tested the RAM sticks by swapping them around in the primary RAM slot.

Seeing no other ideas being mentioned, I guess it's something with the motherboard

Anyone know what T400 MBs tend to sell for?