I picked up a few of those a couple of months ago based on dogie's recommendation.
They absolutely will NOT work to properly cool an S4 in average summer temps across the US.
If it is only one S4, and heavily underclocked (how are you changing the voltage? just curious) and you have it in a room with the AC then sure, they work. Otherwise those fans are for S3, S5, etc, not S4, they are too weak.
Thanks for your reply,
I just remove the voltage values like my s4 (under miner configuration > advanced miner configuration) and yes summer is coming here in Jersey City that I decided to put my two S3+ to a small server cabinet; however, deep in my mind I cannot just let go of my S4 but since you mentioned about summer because sometimes Jersey City's summer can reach up to 90 degrees or 100 at worst with humidity involve I just have to sell it via ebay or if someone here at bitcoin talk would be interested.
I actually bought the machine for about $560 from ebay but I am willing to sell for about $500
or
In exchange with a single S5.
I just dont wanted the machine to be wasted or even burn my apartment down in summer
If you guys know someone who are willing to buy an S4 for $500, please let me know.
Thanks and Regards,
johncban