New replacement computer fan reads 0rpm

Trying to decide what fan to get since these replacements i got are of poor quality... Very untrustworthy seller. so i'm not buying anything from that seller anymore..

Its the next day. Fan still chugging along but slowly and poorly like expected.. Almost no airflow. At twice its rated voltage i doubt its even at 4,000RPM range yet.
the magnet on it seems too weak and bulky/heavy. And the metalic strips that go with the coils are about half the height they should be... Needs an extra 1 link in the chain.

Very thin wires too. Perhaps too thin. and the magnetic field on the magnets is also probably out of wack. With very little strength the fan does not snap to any particular position when not running.. And it stays wherever it stops at.
My 120mm case fan moves exceedingly freely and stops at a magnetic field point. instead of just slowing to a stop.

40mm replacement fan not spinning very freely and makes a bit of a plasticy scratchy sound when you spin it with your fingers slowly. or as it comes to a stop or spins slowly

A 9,000RPM fan gives me lots of room to find the right balance of speed noise and cooling i think..
Do you think i should go for it?

For now the 120mm fan is duct taped to the inside of the grill side of the case

(and with the help of some jumper wires from a breadboard) was able to sneakily add the fan to the plug of fan header by poking them into the same places and combining the jumper wires into the 40mm fan plug and the 120mm fan plug. Almost perfect fit. then wrapped in electrical tape to be hidden.

It runs reasonably cool and quiet for now. Though i'd still like a better fan than the chinese 40mm one. Might get it on the 1st.

New fan Arrived!! Runs correctly at its rated 9,000 RPM literally on the dot (in speedfan it showed precisely 9,000) and blows a ton of air! even at the slowest speed it still blows lots of good air. (Has a sharp cut-off just below 4-5V) but is quiet at the lowest speed and still blows plenty of air to keep my computer cool.. it really ramps up at full speed too. like a mini hair dryer. and theres no vibrational noise or rattling. Speedfan also correctly can register the RPM and control the fan speed without an issue! Great fan! Might buy more of these in the future if I ever need to.

Might need longer screws though... Mine didn't fully reach so I had to go back to the idea of using tape (electrical tape was the right size) and it has no problems.