What is Active PFC?
Active Power Factor Correction improves the power factor value of the PSU by altering the input current wave shape. PSUs with Active PFC can achieve a power factor of 0.99, while PSUs with Passive PFC can only achieve 0.70, and PSUs with no PFC achieve less than 0.60. A higher power factor reduces transmission losses and improves efficiency for power companies, making Active PFC an important feature for the environment.
How can a PFC power supply save energy?
By reducing the volt-amperes your electric utility has to deliver in order to provide a gene power level demanded by the power supply. Much less power is lost in generating useless “harmonics” that unnecessarily load down the AC electrical delivery system.
Are PSUs with multiple +12V outputs more reliable than PSUs with a single +12V output?
Yes, multiple +12V outputs are used to ensure safety protection; each output keeps the current within a safe range. PSUs with a single +12V output generally tend to be older designs and present greater risk because, in the event of a short in any component, there is no over current protection.
Are multiple 12-volt rails better than a single 12-volt rail?
With all the hype about multiple 12-volt rails (ads claim that two rails is better than one, five is better than four, etc.), you’d think it was a better design. Unfortunately, it’s not! Here are the facts: A large, single 12-volt rail (without a 240VA limit) can transfer 100% of the 12-volt output from the PSU to the computer, while a multi-rail 12-volt design has distribution losses of up to 30% of the power supply’s rating. Those losses occur because power literally gets “trapped” on under-utilized rails. For example, if the 12-volt rail that powers the CPU is rated for 17 amps and the CPU only uses 7A, the remaining 10A is unusable, since it is isolated from the rest of the system. Since the maximum current from any one 12-volt rail of a multiple-rail PSU is limited to 20 amps (240VA / 12 volts = 20 amps), PCs with high-performance components that draw over 20 amps from the same rail are subject to over-current shutdowns. With power requirements for multiple processors and graphics cards continuing to grow, the multiple-rail design, with its 240VA limit per rail, is basically obsolete. PC Power and Cooling is once again leading the industry. All of our power supplies now feature a large, single 12-volt rail. The design is favored by major processor and graphics companies, complies with EPS12V specs (the 240VA limit is not a requirement) and is approved by all major safety agencies such as UL and TUV.3
How do I pick a good PSU?
It is not easy for a general user to judge if a PSU is good or not. Here are some principles. • Choose a well-known brand. • Has the PSU passed safety certifications? • Is the wattage number the value for peak output or continuous output? Continuous is better. • Compare the weight with other similar products to see if it is too light. • (Not suitable for passive PFC power supply) • Compare the internal components, if they have size difference. • Does the PSU have the 80 PLUS certification.
How to Make Thunderbolt 3 Storages in Double Performance?
When two Netstor Thunderbolt 3 storage units (model: NA611TB3, NA622TB3, and NA762TB3…etc.) are connected to the same Thunderbolt 3 Mac computer/laptop, you can just use the following connection to get the Doubled Capacity and the Doubled Performance for up to 4200 MB/s between storages and the Thunderbolt 3 Mac.
Equipment Requirement:
。 Two units of Thunderbolt 3 storage
。 A Mac computer with 4 ports Thunderbolt 3
* [Note: 4 ports Thunderbolt 3 ports mean there are two Thunderbolt chips used by a computer; each Thunderbolt 3 chip (two ports) can provide bandwidth up to 2750 MB/s]
Scheme One
Two NA622TB3 present double performance under iMac Thunderbolt 3 ports
* Testing by: NA622TB3 *2, Gloway 2TB NVMe SSD *8, iMac 27”(Mid-2017) *1
Scheme Two
Here is the way to verify which Thunderbolt 3 Mac computer/laptop contains two separate TB3 controllers in support of the above doubled performance.