ocaholic - PSUs > Chieftec Navitas 650W GPM-650C Review

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Preview

Page 2 - Preview

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Delivery and Specifications

Delivery
Cable	Length
1 x ATX 20+4 pin	55 cm
1 x EPS/ATX 12V 8 & 4+4 pin	55 cm
4 x PCI-E 6+2 pin	55 cm
2 x 3 SATA	55, 70, 85 cm
1 x 3 Molex	55, 70, 85 cm
1 x Floppy	15 cm

The delivery of the Navitas 650W is adequate. In total you can provide up to two graphics cards with power, which is perfectly reasonable for a PSU with this wattage.

With this power supply Chieftec is offering a single rail design regarding 12V. In total you get 54A, which can be turned into heat by the graphics cards for instance.

Specifications (according to Chieftec)
Voltage	Current	Power
+ 3.3 V	20 A	100 Watt	650 Watt (Total)
+ 5.0 V	20 A	100 Watt
+ 12 V	54 A	648 Watt
- 12 V	0.8 A	9.6 Watt
+ 5 Vsb	3.0 A	15 Watt

The GPM-650C has been 80Plus Gold certified. This means, that the efficiency of this PSU should be above 87% at 20% load, above 90% at 50% load and above 87% at 100% load.

At this point the feature list:

80Plus Gold
OVP, UVP, OCP, SCP, OPP, OTP
Dimensions (W x H x D): 150 mm x 86 mm x 160 mm
140 millimeter fan
Warranty: 2 Years
Price: ~129 CHF / ~93 Euro

Page 3 - Delivery / Specs

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A Look Inside

You can get a first solid hint for a high quality power supply, when you look at its exterior. In this case we find a nice looking enclosure, which has been well manufactured. Apart from that there is a fan from Y.L. Tech which falls into the high-end category. Removing the top of this unit we quickly see that this PSU is based on CWTs PUQ(G) platform. One can tell this by the green transformer. Despite the fact, that this isn’t the youngest platform it can still be considered state-of-the art. The reason for that is, that the primary side features loss-less LLC conversion as well as interleaved PFC circuitry and on the secondary side we find DC-DC conversion.

First things first: the transient filtering stage, comes with two X and two Y capacitors right behind the AC receptacle. On the main PCB there is a pair of Y caps, another pair of X caps, two CM chokes and one MOV. The transient filtering stage is therefore well done.

Continuing we find two parallel rectifiers. In case of the APFC unit there is one large capacitors from Nippon Chemi-Con, which features 390uF capacity at 400V and they are specified for 105°C. Still on the primary side, we find a thermistor, which has been placed right next to the main transformers. Having the thermistor here makes perfect sense, since the transformers demand cooling.

Meanwhile we’ve arrived on the secondary side. All MOSFETs taking care of the 12V rail are on a small and vertically mounted daughter PCBs. Most of the capacitors are from CapXon, which is a chinese manufacturer. A Weltrend WT7502V chip is taking care of all the protection mechanisms, like for instance OCP and UCP. Furthermore the large daughter PCB hosts the connectors for the partially modular cable management.

Last but not least a few words about soldering quality. Chieftecs OEM (CWT) is making sure, the soldering quality matches the overall quality of this unit, which means it’s pretty well done.

Page 4 - A Look Inside

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Result Analysis and Discussion

Efficiency
Load	Pin(W)	Pout(W)	Efficiency
10 %	80.18	66.33	82.73 %
20 %	149.43	132.10	88.40 %
50 %	362.20	329.68	91.02 %
100 %	735.10	655.39	89.16 %

The 80Plus Gold certification requirements (87% - 90% - 87%) are surpassed especially at 20% Load. The full Load efficiency is a bit higher at 230V AC. This is the case with most of todays PSU's an it mainly originates from the reason of lower losses in the AC filtering stage and the PFC at 230V AC. The 230V AC 100% Load efficiency is 90.68%.

Output Stability
Load	Rail	Loading(A)	Output(V)
20 %	3.3V	2.0	3.3
	5V	2.0	5.1
	12V	9.1	12.2

50 %	3.3V	5.1	3.3
	5V	5.1	5.1
	12V	22.8	12.1

100 %	3.3V	10.1	3.3
	5V	10.1	5.1
	12V	45.6	12.1

The Voltage Regulation of this PSU is very good. It makes use of a DC-DC topology. This means, that the GPM-650C is mainly a 12V PSU and then generates its 5 and 3.3V from 12V. This is a modern approach, and since the Load is mainly on 12V it makes a lot of sense. For almost any PSU which makes use of this topology crossload tests do not present a problem.

Noise
Load
20 %	Noiseless
50 %	well audible

If we listen closer with the power supply, we don't here anything at 20 percent load. The GPM-650C is a semi passive power supply and the fan kicks in, when 35 percent load is reached. It keeps spinning until the load goes below 25 percent. This ensures adequate internal temperatures under all circumstances. When demanding 50 percent load from this unit, the noise level can be described as silent and when there is 100 percent load, the unit is well audible.

Noise/Ripple @ 100% Load
Voltage	Noise/Ripple Vpp
3.3V	0.041
5V	0.038
12V	0.040

The noise values are ok, but they are definitely not excellent. At 100% load we see that the ripple values range from 30mV to 40mV no matter which voltages we're looking at. Since the 12V ripple performance drastically improves with just little less 12V load, we don't judge this as a negative point.

Page 5 - Result Analysis and Discussion

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Conclusion

With the GPM-650C Chieftec released a solid mid-rage power supply. There is a costly AC filtering stage, a high end fan as well as excellent Nippon Chemi-Con capacitors, which - amongst other parts - add up to an overall good product. All the components mentioned comply with hight standards and therefore it's a pity we had to find Chinese capacitors on the secondary side. Nevertheless this is a reliable PSU, which is esily capable of providing power to a mid-range gaming system. The Navitas 650W is an overall solid power supply and apart from that Chieftech is selling it at an attractive price point. We find this unit on Geizhals with prices starting at 92.90 Euro. The only thing we would really like to see changed is the warranty. Chieftech only offers two years of coverage. Other PSU vendors offer up to seven years warranty.

The Chieftec Navitas 650W receives good 4 out of 5 stars.