Question Dell Dimension 8400: How Safe as a Space Heater?


Oct 11, 2009
Long ago I added two storage HDDs to this ancient creature and used it with a Dell 8300 for redundant backups. Some weeks ago upon powering up the 8400 it flashed something on the screen for an instant (no BSOD) and then nothing but beeping and a revving fan. I figured it was a system drive, motherboard and/or video card failure. In any case, while I’ve no wish to spend a cent getting that dinosaur troubleshot and repaired, I’d like to use it under my office desk as a “space heater”. I briefly did this once with my second Dell 8300 and it heated my ~ 11 ft x 8 ft office quite well especially if I closed the door. And it was also delightfully quiet yet producing just the right amount of relaxing white fan noise. But that 8300 works fine as a pc and will instead be using that with my other 8300 for backups.

So I removed the system drive and the two storage SATA HDDs from the 8400 and installed three ultra ancient WD Caviar IDE drives to help heat up the clamshell case. I left the video card in there-whether or not that caused the initial 8400 failure. But when I tested my new “space heater” it again beeped about 4 times but the fan kept on revving much too fast and loud for my liking.

I thought about unplugging the fan but feared that even without a system drive to tell it to do anything that the Prescott CPU would get too hot without a fan and might be a fire hazard. True? If yes, then I thought about unplugging the CPU-if it can be unplugged. Or is it soldered into the motherboard? If no, then how do I unplug it?

BUT as I do not want to have to remove the motherboard, does the CPU and the heat sink on top of it unplug together from the top of the motherboard?

Any other precautions I should take to insure safe operation of the Dell Dimension 8400 space heater?
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I really can't tell if this is a joke or not.
This is one of the most inefficient ways to heat up a space. Small space heaters can be had for under $30 here in the US and are much safer than any of the 'modifications' you mention. Heck, you could even just buy a warm robe to wear for less.
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