If you have a Delta screamer you know that they draw too much power to plug them into motherboard headers. RPM monitoring can be very useful and save you a lot of money, if for some reason the Delta on your heatsink died your CPU would not last very long. Most of the time you purchace a heatsink you get a standard 3 to 4 pin adapter and you are not able to monitor the RPMs. This is a good solution for the power draw problem but you get no RPM monitoring with it. There is however a cheap and easy solution for this which will solve all your problems.
The adapter is a simple little device which has a male and female 3-pin connection and a 4-pin Molex connection.
I will be using a 60mm 7000RPM Delta to test the 3 to 4 pin adapter, this is fan you should not hook directly to your motherboard headers.
All you have to do is plug the fan into the 3-pin connection.
Then plug the other 3 pin plug into your motherboard header and connect the 4-pin Molex plug to one from your power supply and your done.
I booted up the computer and started up Hardware Sensors Monitor. As you can see from the picture the Delta is spinning at 7031 RPM, this little adapter works great.
This adapter is a quick, cheap, and simple thing to use. I really like this adapter a lot, especially compared to the standard ones. The fact that it can let you know if your RPMs drop too low gives you the ability to set some software program to inform you or even shut down your computer which can save your CPU from destruction. There is nothing about this adapter that I do not like, and the price can’t be beat. The adapter costs only $1.15 and if you buy 5 or more shipping is free.
Overall I would give this 3 to 4 pin adapter a 10/10.