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Antec have a wide range of quality products in their portfolio, and their power supplies have always been big sellers. They are updating their mainstream ‘value for money' EarthWatts range with two new models, a 650W and a 750W power supply. Today we are looking at the 650W model, with the 750W review to come very shortly.
The EarthWatts 650W is supplied without a power cable, because Antec see these units as ‘upgrade' models. Antec have came under fire for not supplying the power cable but after speaking with them, they feel that people already have plenty of cables and this is an unnecessary extra. I think there is also a ‘mother earth' angle to it, but I don't really understand how the removal of a power cable would help anything, so ill just move on.
So what's new? Well Antec are still using Delta as their OEM but they are now 80 Plus Bronze Certified. The new units are ‘green' and they have received some performance improvements. The 750W also has a larger cooling fan, but more on that in the next review.
Earthwatts 650W overview:
- 650 Watts of continuous power
- Nvidia SLI certified, ATI CrossFireX certified
- 80 Plus Bronze Certified – up to 88% efficient
- Two +12V rails
- Up to 100% power available on +12 rails
- Quiet 120mm fan
- ATX 12V version 2.3 and EPS12V version 2.91 compliant
- Active PFC with PF: 0.99
- MTBF: 100,000 hours
- Meets 2010 EUP requirement: 5Vsb < 1W
- Safety: cUL, TUV, CE, CB, FCC, C-TICK, CCC, BSMI, Gost-R
The Antec EarthWatts 650W arrives in the traditionally designed Antec box, with accented yellow stripe down the edge.
The bundle is spartan with 4 mounting screws and a little information pamphlet included. The PSU is protected in a bag with cardboard pieces on either side. This is not a modular design.
The EarthWatts 650W is actually a rather attractive little unit, finished in a camouflage style green paint. The older unit was gray which was rather bland.
The rear of the unit is vented to allow for good airflow. There is a power switch next to the cable connector port.
The 120mm fan takes centerstage at the top behind a black grill. No gaudy multicoloured concepts for this unit, just plain old black.
All the cables emerge from an single outlet. It is rubber housed to offer some protection from fraying.
| Antec EarthWatts 650W Power Supply | ||||||
|
DC Output
|
+3.3V
|
+5V
|
+12V1
|
+12V2 |
-12V
|
+5Vsb
|
|
Max Output
|
24A
|
24A
|
38A
|
38A |
0.5A
|
2.5A
|
This design has two +12V rails, offering 38A.
| Cable | Amount |
| MB 20+4 pin | x1 |
| CPU 4+4 pin | x1 |
| PCI E 8 pin (6 pin +2) | x2 |
| Sata power connectors | x7 |
| Peripheral 4 pin (molex) | x5 |
| Floppy connector | x1 |
The fan is a Protechnic ‘Magic' MGA12012HB-A25 and we have very little information on the specifications. We do know it is a double ball bearing unit and that the sister unit the ‘O25' is rated at 80cfm.
The Delta design is well laid out and had several heatsinks to help with component cooling.
The supply is using a primary 330uf 420V Samxon capacitor which is rated to 85c. The design is Active PFC and offers over current, over voltage, short circuit, over power and over temperature protection.
Additional technical assistance: Peter McFarland and Jeremy Price.
Correctly testing power supplies is a complex procedure and KitGuru have configured a test bench which can deliver up to a 2,000 watt DC load. Due to public requests we have changed our temperature settings recently – previously we rated with ambient temperatures at 25C, we have increased ambient temperatures by 10c (to 35c) in our environment to greater reflect warmer internal chassis conditions.
We use combinations of the following hardware:
• SunMoon SM-268
• CSI3710A Programmable DC load (+3.3V and +5V outputs)
• CSI3711A Programmable DC load (+12V1, +12V2, +12V3, and +12V4)
• Extech Power Analyzer
• Extech MultiMaster MM570 digital multimeter
• SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa)
• Digital oscilloscope (20M S/s with 12 Bit ADC)
• Variable Autotransformer, 1.4 KVA
We are combining 12V output into a single result.
|
DC Output Load Regulation
|
||||||||||
|
Combined DC Load |
+3.3V
|
+5V
|
+12V
|
+5VSB
|
-12V | |||||
|
A
|
V
|
A
|
V
|
A
|
V
|
A
|
V
|
A | V | |
|
152W
|
2.07
|
3.33
|
2.02
|
5.09
|
10.03
|
12.03
|
0.50
|
5.04
|
0.20
|
-12.05
|
|
270W
|
3.02
|
3.33
|
3.01
|
5.07
|
19.05
|
12.02
|
0.50
|
5.02
|
0.30
|
-12.04
|
|
400W
|
4.04
|
3.32
|
5.01
|
5.06
|
29.21
|
12.01
|
1.00
|
5.01
|
0.30
|
-12.04
|
| 523W |
6.00
|
3.30
|
7.08
|
5.03
|
38.14
|
11.97
|
1.50
|
4.99 |
0.30
|
-12.02
|
|
652W
|
8.03
|
3.29
|
9.02
|
5.03
|
48.31
|
11.94
|
2.50
|
4.97
|
0.30
|
-12.02
|
Output load regulation is good from this supply, holding all primary rails within 2.5% of the nominal voltage.
| ANTEC Earthwatts 650W | Maximum Load |
| 713.4W |
The power supply would shut down at 713.4W, gracefully. We found the protection circuitry to work very well.
Next we want to try Cross Loading. This basically means loads which are not balanced. If a PC for instance needs 500W on the +12V outputs but something like 30W via the combined 3.3V and +5V outputs then the voltage regulation can fluctuate badly.
| Cross Load Testing | +3.3V | +5V | +12V | -12V | +5VSB | |||||
| A | V | A | V | A | V | A | V | A | V | |
| 590W | 1.0 | 3.31 | 1.0 | 5.04 | 48.0 | 11.89 | 0.2 | -12.05 | 0.50 | 5.02 |
| 145W | 12.0 | 3.27 | 15.0 | 5.01 | 2.0 | 12.03 | 0.2 | -12.03 | 0.50 | 5.00 |
The Antec supply did a pretty good job during our intensive cross loading test, and the supply remained stable within the stated tolerances.
We then used an oscilloscope to measure AC ripple and noise present on the DC outputs. We set the oscilloscope time base to check for AC ripple at both high and low ends of the spectrum. ATX12V V2.2 specification for DC output ripple and noise is defined in the ATX 12V power supply design guide.
|
ATX12V Ver 2.2 Noise/Ripple Tolerance
|
|
|
Output
|
Ripple (mV p-p)
|
|
+3.3V
|
50
|
|
+5V
|
50
|
|
+12V1
|
120
|
|
+12V2
|
120
|
|
-12V
|
120
|
|
+5VSB
|
50
|
Obviously when measuring AC noise and ripple on the DC outputs the cleaner (less recorded) means we have a better end result. We measured this AC signal amplitude to see how closely the Antec unit complied with the ATX standard.
| AC Ripple (mV p-p) | ||||
| DC Load | +3.3V | +5V | +12V | 5VSB |
| 152W | 10 | 5 | 15 | 10 |
| 270W | 10 | 10 | 25 | 15 |
| 400W | 15 | 10 | 35 | 15 |
| 523W | 20 | 15 | 45 | 15 |
| 652W | 25 | 15 | 55 | 20 |
Ripple results all fall within the tolerance guidelines above, with the +12V hitting a maximum of 55mV under full load. +5V hits 15mV and +3.3V peaking at 25 mV.
|
Efficiency (%)
|
|
|
152W
|
83.78
|
|
270W
|
87.56
|
|
400W
|
88.13
|
|
523W
|
87.32
|
|
652W
|
83.76
|
These results are strong for an 80 Plus Bronze rated power supply, peaking at just over 88 percent at 50 percent load. At full load the efficiency drops to around 84 percent.
We take the issue of noise very seriously at KitGuru and this is why we have built a special home brew system as a reference point when we test noise levels of various components. Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on components we are testing. It also brings us slightly closer to industry standards, such as DIN 45635.
Today to test the Power Supply we have taken it into our acoustics room environment and have set our SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa) one meter away from the unit. We have no other fans running so we can effectively measure just the noise from the unit itself.
As this can be a little confusing for people, here are various dBa ratings in with real world situations to help describe the various levels.
KitGuru noise guide
10dBA – Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA – High Quality Computer fan
40dBA – A Bubbling Brook, or a Refridgerator
50dBA – Normal Conversation
60dBA – Laughter
70dBA – Vacuum Cleaner or Hairdryer
80dBA – City Traffic or a Garbage Disposal
90dBA – Motorcycle or Lawnmower
100dBA – MP3 Player at maximum output
110dBA – Orchestra
120dBA – Front row rock concert/Jet Engine
130dBA – Threshold of Pain
140dBA – Military Jet takeoff/Gunshot (close range)
160dBA – Instant Perforation of eardrum
|
Noise (dBA)
|
|
|
152W
|
27.8
|
|
270W
|
28.4
|
|
400W
|
30.6
|
|
523W
|
32.4
|
| 652W | 34.8 |
This is a really quiet power supply, becoming audible only in the last 20% of its rated power output. Generally it is difficult to hear, rating under 30 dBa at 50 percent load.
|
Temperature (c)
|
||
|
Intake
|
Exhaust
|
|
|
152W
|
35
|
38
|
|
270W
|
35
|
39
|
|
400W
|
38
|
45
|
|
523W
|
42
|
50
|
|
652W
|
45
|
54
|
The large 120mm ‘magic' fan helps to maintain fairly decent internal temperatures, rising to a 9c above ambient intake threshold at full load.
|
Maximum load
|
Efficiency
|
|
715.8W
|
82.3
|
Pushing the PSU above its rated limits generates an efficiency level of around 82.3%. This is not a viable ‘real world’ situation, but its interesting nonetheless.
As a value oriented unit, it is hard to find fault with the Antec Earthwatts 650W power supply. The revamped Delta design is effective, delivering solid load regulation and very impressive levels of efficiency for an 80 Plus Bronze certified product.
Ripple and noise suppression is pretty good, with the unit peaking at 55mV on the 12V output when under full load, well within rated tolerance levels. We don't have the older model handy to compare directly against, but we do know that it was a rather drab looking gray colour. The Camouflage style green looks really different and stands out in the crowded marketplace. Not everyone will warm to it, but I thought it was rather appealing.
We would like to see a modular design, as this could find its way into many media pc's, but we have to bear in mind the target market and price point. The cables are unfortunately unsleeved which is slightly disappointing.
These power supplies are not sold by Antec to compete at the upper price points with class leading performance. This product should hit UK retail at £60-£65 including VAT, making it a very strong value for money purchase. In the states they retail for $65.
Pros:
- solid performance
- good efficiency
- cross loading results are positive
- green paint has improved the appearance
- price point is very competitive
Cons:
- cables are not sleeved
- non modular
KitGuru says: For the price, it is hard to beat.
