Alert! Chipset heat sink not detected, system halted! (5/25/08) With four websites and two portfolios begging me to work on them, right now, and the monthly update for Desert Exposure just days away . . . This. Was. Unacceptable.

I rebooted my machine (a Dell 4600C) to finish an XP update cycle and that's the message it gave me. 2 seconds into its boot cycle, it just stopped. Again. Then again. And again. I guessed it really meant it. So I took out my soldering iron and went to work.

OK, back up a minute. First I went and poured a cup of coffee and stared at my mutinous hardware. Then I got on the net using an iBook I keep around to check websites for cross-platform performance. I searched for the error message and found several threads devoted to it. This problem seems endemic to Dell 4600C's. A dreadful number of threads end with new machines or at least new motherboards after frustrating adventures with Dell tech support and forays to local computer shops.

The proximal cause of the message is the failure of a spring holding the chipset heatsink (not the CPU heatsink) in place. The spring is mechanically important (it keeps the heatsink in place and in firm contact with some hot and critical chip on the momboard) as well as electrically significant (it connects contact points "HS1" with "HS2"). The spring hooks into "stirrups" which plug into HS1 and HS2.

Break the electrical connection, you get the message. Usually, one of the stirrups turns loose. The question is: does the failure of the spring's connection betoken overheating or it just a mechanical failure? I'm betting the latter, but figured I'd do what I could for both issues, just in case.

OK. So. As it happes I have an older 4600C sitting here handy for comparitive anatomy lessons. (Lightning destroyed something important in it and I bought the one I currently use on eBay for about $200. I had time to replace the lightning-struck machine without disappointing clients. Not so this time. Yes, there were other used 4600C's out there; no, I don't have time to buy and order and swap drives and reconfigure another one; and no, I don't want to keep pouring money into a 4-year old computer when I'd rather buy a faster/better/newer one when Dell puts them on sale or even better, buy one from Eric when he starts selling customized top-end machines for photographers.)

I opened up the case, and sure enough: the spring was sprung. It was missing the stirrup which anchors it at HS1. I opened up the older machine to verify how it was supposed to look.

Because every other thread devoted to this problem ends in sorrow and mine does not, I decided to document the fix for the next schmuck who gets that message, because the fix is easy and fast (had mine going in 2 hours, including time to go buy Arctic Siver heat transfer grease at Radio Shack -- they didn't carry the heat transfer epoxy I really wanted). Looky:

Properly mounted chipset heatsink in a Dell 4600C. Note hold-down spring connecting two points on the motherboard.		Spring sprung on 4600C reporting "chipset heatsink not detected". Circled connection, sans hold-down hook, is HS1. Spring is still attached (uselessly) at HS2.

You need to provide both functions of that spring to fix the problem: you have to reconnect HS1 and HS2 electrically, and you have to make sure the heatsink is held firmly to the momboard. If it comes loose, the chipset will fry a few seconds after you turn the machine on (so I read).

To complete the circuit from HS1 to HS2, telephone wire and a solder gun will do. Thank you Dr. David Close of the ETSU physics department for teaching me how to solder wire to a circuit board (insert wire, heat wire, touch hot wire with well tinned tip of soldering iron and a thin strand of solder; metal flows down the wire and into the hole pretty as you please -- do this gently, quickly, and as deftly as possible; if you pretend to know what you are doing, you are more likely to get away with it).

In the absence of the spring, the heatsink came off easily enough.

Then I used Arctic Silver thermal cleaner to clean up both the heatsink and the polished face on the exposed chip. You can use alcohol if you don't have the cleaner. And use thermal grease and a jury-rigged hold-down if you don't have the epoxy. I know because I actually did this fix twice -- once in a hurry using vodka as a cleaner, thermal grease to insure thermal contact, and a tennis-ball-sized wad of aluminum foil compressed between the computer case and the heatsink to keep the heatsink in place while I finished up jobs under deadline. At the same time, I ordered the exact stuff needed (Arctic Silver thermal cleaner and Arctic Silver Alumina epoxy) and when it arrived, I re-did the fix for real.

The red line indicates the connection needed. The chip is shown still cruddy with old thermal grease -- i.e., as yet uncleaned. I don't have any photos showing it in its gleaming state after cleaning.

Voila! Chipset heatsink epoxied in place (negating the mechanical need for the unused but still present spring) and telephone wire soldered in to provide the electrical connection between the two circuit points.

One week on: so far, so good.

Three Five months on: no problems.

[Note: I'm using the computer with the CPU box flat on the desktop now, rather than standing up as a tower. I had the room and saw no reason to stress the bond; it would probably be fine upright.]

:: back to the slow motion blog ::