Summary: This fan is very loud at maximum speeds, but it works great for moving lots and lots of air in or out of your case. You could also use it with your processor's heatsink (if it is compatible of course) so that you can really cool down your processor and extend its life, or even overclock it.
Summary: Not a quiet fan by any means, but it moves tons of air for its size. Ideal for servers or for people who just want to move air and don't care about noise. Look at the Vantec Stealth series for quiet fans in this size.
Summary: This is the second greatest fan for installing on a socket type heat sink, the first greatest being it's "sister" the Vantec Tornado 92mm (P/N:TD9238H) which moves air at an unbelievable 119CFM for just 4 more DBA. I have seen this 80mm fan turn cpu temps down anywhere from 4-20 deg.
Summary: This is definately a server fan. The 80mm is thick and blows hard. 55dba is pretty loud. Of course, ideally suited for a server case. Vantec fans are excellent and we highly recommend them at the shop.
Summary: This fan comes with a fan grill, a 3-pin connector and also a 4-pin connector. The width of this fan is much greater than usual fans. This fan pushes a lot of air while sacrifing silence. It uses a lot more power because of this. Overall, a nice product to maximize airflow in your case.