Hi guys, just new here!
This is my experience with the 1250.
After two years of service it started to behave abnormally. Fans at 100% all time, high temperatures on the core...rattling noise from one of the pumps.
Grid software also had issues with Windows 10, even after .NET 2.0 activation.
I fully disassembled the unit, to find weird things: first, pump #2 was not properly functioning, making resistance to the water flux. Second, much worse, the waterblock was full of dirt, like limestone powder. I think the coolant had some kind of degradation. The internal copper thin blades were obstructed, so the coolant could not properly do the job. Third, the pumps are connected to the 12v via 2 pins cable, but on the PCB they HAVE the third contact for rpm measurement...just not connected..
Fourth, the two fans are connected through a split cable, one with all four pins and the second without the rpm pin...
Repair and improvements:
- Coolant replaced with pure water. I also went through a long process to eliminate all bubbles.
- Pumps connectors replaced soldering standard 3 pins molex, powered directly by the motherboard, with possibility to monitor and adjust speed, like a conventional fan
- PWM fans both connected to 4 pins headers on motherboard. Again, the motherboard takes care of them.
- Waterblock rectified and mirror-polished, mounted WITHOUT thermal paste.
The cooling system now is under full control of Asrock utility. Pumps can operate between 1500 to 2200 rpm, but minimum speed is more than enough as they start to rattle as soon as the speed goes up. At idle the CPU reach only 28 °C, a temperature never seen even when the 1250 was brand new.
The fans still behave strangely: one turn from 650 to 2300 rpm, but without a linear ramp: from level 1 to 7 it slowly increase speed, and at 8 goes suddenly to 2200.
The second one starts from 1600 and increase linearly to 2300, but there is no way to go under 1600 rpm, which is quite noisy.
What should be the range of a good PWM fan?
AMD Fx-9590. You know the beast, with its 220 W of TDP.
Asrock FX990 Extreme 9