So, Ludigel plugs in his 2005 Acer Game PC, does not even turn it on, but then there is a quite loud bang, much like a light bulb imploding (so don't nag if it was an im- or explosion) and the PC refuses to turn on. Graphics cards smelled funny, took it out, plugged in PC (now also with new power supply to make sure), disconnected all other stuff like HDD and DVD-ROM and .... it turns on, the CPU fan starts turning and then the fan stops again. Most likely motherboard fried.
I had the same back in 2004 when a PC actually started to burn (a cable connected to the internal speaker), which also friend the motherboard and ruined the interface to the graphics card (as a diagnosis PCI card revealed which my wife knows how to handle). The apartment those days had flickering lights, so that might be a reason.
Before that, the ACER and another older PC often did not turn on, had to take out RAM and graphics card and then plug them back to get them started.
I've had it with PCs, I bought 3 notebooks over the last year and do not need anymore PCs in Taiwan. Must be the damned moisture here. Notebooks cope with humidity and bad power much better, knock on wood.
So rot in hell, damned Acer, as you lie there, shiny and new (at least looking like it) on the floor, with your blue motherboard and matching blue graphics card. ROT IN HELL!
HDD makes a good enclosure for backups now with a SATA cable and power thingy.