What does it mean bro? It means that the PWM logic never letting the cards run at temperature such high like 94 degree. Whenever, they are closer to that, the logic is downclocking it to reduce the tekmperature. They run at 95 degree means they are running at it for some times, not just touching it and then get reduced. However, now the R9 290 Fan runs at 45% and the PWM logic bug hyas been updated in the Catalyst Driver. So heating issue is not coouring any more.
Yes.. the drivers have infact been updated to increase fan speed, but this does not reduce temperatures because the card continues to run at 94C. However, the increase in fan speed has improved cooling, which allows the card to higher frequencies... but it's still running at 94C
As i have repeatedly said, AMD allows the cards to run upto 94C. However, once this temp has been reached, the fan speed is increased (till the max depending on the BIOS.. ). However I think for the R9 290 cards, the max fan speed is around 2200 rpm (or 2500), im not sure. After this it will throttle be by downclocking in decrements.
This means FAN SPEED ~ frequency attain = performance.
Faster your fans... more cooling.. higher clocks...
Consider a custom card.. the cooler is very good.. so as the card warms up to say 80C, the card runs at it's max 1Ghz clock.. now as it heats up even more.. the fan speed increases.. and temps decrease.. and stabilize..
But the problem is the stock cooler is not good enough, because of which the card runs at it's max allowed 94C to try at attain it's max frequency.... however it is throttlign a bit.. which is why it runs at ~900Mhz.
It prioritizes frequencies first.. then fan speed.. and controls all of this according to temperature.
So it tries to run at 1ghz.. as soon as it hits it's temp limit i.e. 94C.. it increase fan speeds..
So if the cooler was good it would run at 1ghz at all times with lower fan speeds with a temp a bit lower than 90C
This is because the temperature here is limiting performance of the R9 290.. There simply isint enoguh thermal headroom to allow the card to run at its max frequency.. which is why it's down clocking and reducing performance..
AMD's update increases fan speeds to improve cooling. This could lead to 2 things:
Same frequency but with lower temps.. Or same temps with higher frequency.. AMD went with the 2nd option..
Multiple power supplies shouldnt be an issue.. All you need for a power supply to start is to connect those 2 pins on the 20+4 pin header.. So you could always add a switch to the outside of your cabinet and use it to control your secondary PSU.
Or you could even connect the wires to the same cable of the other PSU.. like you know.. in parallel.. But that'll be more messy..