4.71V, on what should be 5V. I'm actually surprised Nyx ran at all with that. SpeedFan doesn't report much better:
So time to replace the power supply. Nyx currently has an Antec TruePower 430, which was never actually intended for it. I bought that one back in 2006 to upgrade Achilles - that system outright killed one PSU and tried to melt a second - and when I first spec'd out Khaos (the predecessor to Nyx) I included an Antec NeoHE 550 (and actually received the 650W variant due to a mixup at Overclockers). However that one developed fan problems and as an interim measure I dropped the 430W supply back in.
This was many years ago, back when Khaos had a much smaller hardware loadout...
Anyway, these days Antec seem to have diminished in the market so I've plumped for a Seasonic Focus+ Gold 650FX - they seem to be consistently well rated by Anandtech, and are competitively priced with the likes of Antec and Corsair. The 430W existing supply was likely marginal for the loading in Nyx, so the hope is 650W will be plenty.
On with the upgrade! Nyx is an absolute rats nest of cabling inside - and to think when I bought this case in 2007, it was considered one of the roomier ones on the market.
Some time later, after arguing with the screws holding the old PSU in. One of the main reason I bought this particular case was the removable motherboard tray.
Away with ye! Or not - it'll probably end up in the spares bin.
The replacement supply is fully modular which makes getting the cables sorted out much easier. The main ATX feed is still ridiculously long though.
Finally got all the cables squeezed back in, and Nyx wired back up (not seen: the other rats nest of cables, hidden behind the motherboard tray). It booted first time which makes for a pleasant change.
As always, there are some spare parts left over - a collection of no-longer-needed adapter cables. Though I did have to dig out a molex-to-molex-and-floppy splitter - the new PSU was one molex short (or alternatively one floppy short, depending on whether or not I used its adapter cable).
So did the upgrade work? Well, SpeedFan now reports:
And those numbers have been rock-stable for the past few hours, while previously they would fluctuate a bit under load. Result!