Delia Ambrose

Normal, and it's mostly the shape of the tank.

The sender is a float on an arm that sweeps through an arc, and the tank is not a neat cylinder. It's a moulded shape that fits around the exhaust, the suspension and the floor pan, so it's wide in some places and narrow in others. Where the tank is wide, burning a few litres barely lowers the level and the float hardly moves. Where it's narrow, the level drops quickly for the same amount of fuel.

On top of that the float can only travel so far, so a genuinely brimmed tank holds more fuel than the sender can distinguish from full. That's your first 80 km.

Manufacturers also deliberately damp the signal and bias the top of the gauge, partly so it doesn't swing around every time you go up a hill and slosh the fuel to one end.

Right. And there's usually a deliberate reserve below the empty mark, often 5 to 8 litres, because running a fuel pump dry damages it. They'd rather you thought the car was pessimistic than have you calling for a tow.

You can sometimes feel which side dropped. If the water goes hot and the flow stays the same, you lost cold. If it goes hot and weak, something is compensating and partially succeeding. Not useful information in the moment when you're plastered against the wall, but satisfying afterwards.

Sounds like a dead stick to me. RMA the kit, don't waste a week on BIOS settings.

While you're in there, make sure the card has two separate PCIe cables from the PSU and not one cable with a daisy chained second connector. That won't cause your symptom on its own but it makes every other symptom worse.

Cold boot only, fixed by reseating, that's contact. Two things to do in the same session: wipe the gold fingers with 99% isopropyl on a lint free cloth until the cloth comes away clean, and then support the card. A 1.3kg card hanging off the bracket with nothing under the far end levers the top edge of the fingers out of the slot, and metal contracting overnight is enough to finish the job.

A $6 support bracket or even a stack of foam under the end of the card for a week will tell you whether that's it.

One thing worth doing anyway on that socket: a contact frame. The stock LGA1700 retention mechanism bends the IHS very slightly concave and people routinely see 5-8C from swapping it for a flat frame. It's a 15 minute job and about the price of a tube of paste.

If the extractor slips too, drill the head off. Pick a bit roughly the diameter of the head, drill straight down until the head separates, and the bracket lifts away. Then you've got a bare shank sticking out of the frame that you can grip with pliers and wind out properly.