>"Putting the GPU into an oven and baking it for a while fixed the problem for a few days by resoldering cracked solder points, but then it returned. This is probably related to the switch to lead-free solder in 2006, which is more brittle."<p>no, no, NOOOOOOOOOOOOO<p>Nvidia makes faulty GPU chips for 9 years now (underfill between die and bga carrier package). Starting with G84, up to at least Fermi, EVERY SINGLE GPU will die from thermal stress is used extensively at high temps. This is very well documented in numerous lawsuits that forced Nvidia, DELL, APPLE and other manufacturers to do repeated expensive recalls.
The memmap trick is pretty clever, though I wonder what the syntax is to make grub reserve multiple unrelated bytes instead of a 1-byte contiguous 'chunk.'
> 7 case fans<p>This sounds like too many fans to me. Fans can even have negative side effects on the air flow. Usually you want one flow from the front to the back. In some cases just the PSU fan is enough. You generally only want 120mm fans, as airflow rises faster than noise with size.
The first post: No, Nay, Never replace with "some old caps".
At first, try to determine WHY the caps failed. E.G. Is there something exceedingly hot around, and can you fix it?
Second, the best thing to do is take caps with higher Voltage rating, because many manufacturers cut the margin exceedingly close, resulting in premature failiure.
Third, due to the heat in the Power supply, rather take Aluminum-Caps, not Tantalum caps. They have the tendency to start burning.
Fourth, look at how the caps are arranged. When there are some in Parallel, take normal ones. Else, you must take Low-ESR ones.
> <i>"When you open up hardware you have to be careful about electric shocks. I never received one, but especially power supply units (PSUs), which were the broken parts inside of my displays, can store a high amount of energy for a long time after disconnecting them from power."</i><p>I did some Googling a few months ago on this subject to clear it up for myself and found a bunch of information that strongly suggests the above line of thinking is very very wrong: it's <i>CRTs</i> that store massive amounts of energy for ages - they do this to store energy for future warmups, so the necessary surge of power can partially come from the CRT itself. So this is a design feature.<p>Most current PSUs have bleed resistors to drain the internal capacitors, and if I understand correctly, the short/very quiet high-pitched squeal you hear when you disconnect a PSU is the high-frequency oscillator circuit rapidly winding down as the charge in the capacitors is drained (I recommend a quiet room/environment to test this). This happens within about a second or so on the low-wattage PSUs that I have here.<p>If putting a screwdriver across the capacitors in a PSU produces an arc 5 or 10 seconds after that PSU is off, I'd be very very surprised.<p>The "PSUs KILL" line has been touted by CRT techs, probably from a time when bleed resistors and other safety measures weren't as prevalent. Well, it worked... and now we believe everything's dangerous. I personally feel a lot more confident eg swapping a fan in a PSU - I hear the squeak (in the PSUs I have) and know that it's now safe to work on.<p>With the above said, if I were tinkering with an unknown PSU, or especially a cheap Chinese OEM supply in a set-top box or similar device, I'd probably poke everything with a big insulated metal stick before I worked on/near it.<p>Of course, standard disclaimers with this type of info applies - <i>definitely do your own research before trusting the above!</i><p>If any engineers/electricians/similar can chime in here and confirm/disagree that would be great.