It is well known that Rosewill is a company that started off as a subsidiary of Newegg, originally focused on marketing simple bits and hardware at very competitive prices. Rosewill grew vastly in a relatively short time and fledged into a stand-alone company with an impressive range of products. Today, Rosewill offers a myriad of products from simple cables and adapters to advanced computer hardware, home appliances and office products. The sheer number of products Rosewill markets today is makes ones mind boggle. Nevertheless, the company is strongly localized, with their products readily available only in the North American markets. Rosewill is making moves to enter other regions and some, but not all, of their products can also be found in Southeast Asia, Japan, China and Australia.

Rosewill's marketing policy is strongly based on the offering of low cost products, not differentiation. Despite their very large range of products, generally speaking, most of them are designed so as to compete in terms of value, with the company and the designers trying to outprice the competition, not outperform it. Rosewill will commonly minimize investing on features they deem unnecessary, such as aesthetic improvements or innovative elements, trying to deliver products of similar quality and performance as the competition at a lower price. Today we will be having a look at the best PSU series Rosewill currently offers, the Quark, the embodiment of Rosewill's business stratagy.

On paper, the specifications of the Quark PSUs are very impressive, with high current lines and 80Plus Platinum efficiency. As a matter of fact, Rosewill went through the trouble of getting official 80Plus certifications for every unit of the series, not just one or two models. All of the Quark PSUs also come with a five-year warranty. However, there are no fancy features such as lighting, USB interfaces and power meters. Rosewill supplied us with four out of the six units of the series, the 750, 850, 1000 and 1200 Watt models, so we are having a very thorough look at the series in this review.

Rosewill Quark 750W - Power specifications ( Rated @ 40 °C )
AC INPUT	100 - 240 VAC, 50 - 60 Hz
RAIL	+3.3V	+5V	+12V	+5Vsb	-12V
MAX OUTPUT	22A	22A	62A	2.5A	0.3A
	120W		744W	12.5W	3.6W
TOTAL	750W

Rosewill Quark 850W - Power specifications ( Rated @ 40 °C )
AC INPUT	100 - 240 VAC, 50 - 60 Hz
RAIL	+3.3V	+5V	+12V	+5Vsb	-12V
MAX OUTPUT	25A	22A	70A	2.5A	0.3A
	120W		840W	12.5W	3.6W
TOTAL	850W

Rosewill Quark 1000W - Power specifications ( Rated @ 40 °C )
AC INPUT	100 - 240 VAC, 50 - 60 Hz
RAIL	+3.3V	+5V	+12V	+5Vsb	-12V
MAX OUTPUT	25A	25A	83A	2.5A	0.3A
	120W		996W	12.5W	3.6W
TOTAL	1000W

Rosewill Quark 1200W - Power specifications ( Rated @ 40 °C )
AC INPUT	100 - 240 VAC, 50 - 60 Hz
RAIL	+3.3V	+5V	+12V	+5Vsb	-12V
MAX OUTPUT	25A	22A	100A	2.5A	0.3A
	120W		1200W	12.5W	3.6W
TOTAL	1200W

.

Packaging and Bundle

Rosewill supplies the Quark series PSUs in typical, sturdy cardboard boxes. All of the boxes share the same artistic theme, a conceptual shape of a few quarks on a black background, with information and specifications printed on the sides and back of the box. Only the 750W version has a slightly smaller box, hinting that this unit has significant differences in comparison to the more powerful models.

The Quark series PSUs are not accompanied by the most generous bundle that we have ever seen, but it is better than Rosewill's usual frugal bundle. Inside the box we found a very basic manual, an AC power cable, a few short cable ties, four black thumbscrews and a nylon pouch with the modular cables stored inside it.

To our surprise, the modular cables of the Quark PSUs are made of simple, color coded wires bounded with black sleeving. These are the most basic cables available and are usually being used by the budget segment of the market, for small PSUs designed for the average home/office PC.

	Rosewill Quark 750W	Rosewill Quark 850W	Rosewill Quark 1000W	Rosewill Quark 1200W
Connector type	Modular	Modular	Modular	Modular
ATX 24 Pin	1	1	1	1
EPS 4+4 Pin	2	2	2	2
EPS 8 Pin	-	-	-	-
PCI-E 6+2 Pin	4	6	8	8
PCI-E 8 Pin	-	-	-	-
SATA	8	10	12	15
Molex	4	4	5	5
Floppy	1	1	1	1

External Appearance

Rosewill went with the common "black goes with everything" approach for their Quark series units. The otherwise simple chassis is sprayed with a textured black paint that creates a sandstone-like visual effect. Instead of installing a removable finger guard, Rosewill cut the top cover to resemble a warped spider's web. There are no stickers or decorations on the sides of the chassis, the sticker with the specifications of the PSUs is placed at the top side of the units. The three most powerful Quark PSUs share the same exact chassis, while the 750W version is only slightly shorter.

 

The rear side of the PSUs is relatively uninteresting, with just a typical on/off switch and an AC power cable connector to be found there. Perhaps the only noteworthy observation is that the 750W unit has a smaller switch, as the larger units naturally have to cope with a larger input current.

While it is not strange for the rear side of these PSUs to be very similar, their front sides are peculiarly identical as well. All of the units share the same number of connectors, even though the smaller units do not come with enough cables for them. All of the connectors are black, with the exception of the PCI-Express connectors, which are blue. There are also six self-test LEDs near the top, five for the main voltage lines and one for the "Power Good" signal. These can be used to diagnose basic PSU issues.

Internal Design

Another difference between the 750W Quark and the more powerful versions is the fan. The 750W version has a Yate Loon D14BH-12 fan installed, a very powerful 140 mm fan, with a ball bearing engine and a maximum rotational speed of 2800 RPM. For the more powerful models, Rosewill went with a slightly smaller Young Lin Tech model, the DFS132512H, a 135 mm fan with a "hybrid" self-lubricating bearing and a maximum rotational speed of just 1700 PRM. Why Rosewill is installing such a powerful fan in the smaller models eludes us, as units capable of 80Plus Platinum efficiency with such a power output do not require these levels of airflow.

A glance on the insides of the Quark series PSUs instantly reveals that the 750W version is based on a similar, yet different platform than the rest. All are made by Enhance Electronics, with the 750W based on the 13XX Platinum platform and the more powerful units on the boosted 13XX Platinum GT platform. The 750W version has similar but notably smaller heatsinks and main transformer, while the secondary conversion stage MOSFETs can be seen from the top side of the main PCB, next to the transformer. The three larger PSUs have a larger secondary side heatsink and the secondary conversion MOSFETs are placed underneath the main PCB.

There is virtually no design difference between the 850W, 1000W and 1200W PSUs. Only the size and suppliers of the components change, with the mere exception that the 850W PSU has one input bridge rectifier and the larger units have two, with an extra smaller heatsink sandwiched between them.

The filtering stage of the 750W version consists of four Y capacitors, two X capacitors, two filtering inductors and a surge suppression MOV. Panasonic supplies the APFC 450V/560μF capacitor and all of the secondary side electrolytic capacitors come from Nippon Chemi-Con. Teapo supplies the polymer capacitors.

Enhance boosted the filtering stage of the 850W-1200W units slightly by adding two extra X capacitors. Rosewill's choice of component suppliers with these three models is very messy, hinting that the company is using whichever supplier is available and cost-effective at the time. The 850W version has its 420V/330μF primary capacitors supplied by Matsushita, its secondary side electrolytics are a mix of Nichicon, Unicon, Nippon Chemi-Con and Rubicon products, with Teapo supplying the polymers. The 1000W version came with two Nippon Chemi-Con 450V/390μF APFC capacitors, a mix of Nichicon, Unicon, Nippon Chemi-Con and Rubicon electrolytic capacitors, with Teapo and Dura Tech supplying the electrolytics. Finally, the 1200W version comes with Matsushita 420V/470μF APFC capacitors, a mix of Unicon, Nippon Chemi-Con, Nichicon and Dura Tech electrolytics, and another mix of Teapo, Nichicon and Dura Tech polymer capacitors. 

Cold Test Results

For the testing of PSUs, we are using high precision electronic loads with a maximum power draw of 2700 Watts, a Rigol DS5042M  40 MHz oscilloscope, an Extech 380803 power analyzer, two high precision UNI-T UT-325 digital thermometers, an Extech HD600 SPL meter, a self-designed hotbox and various other bits and parts. For a thorough explanation of our testing methodology and more details on our equipment, please refer to our How We Test PSUs - 2014 Pipeline post.

Efficiency

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

Power Losses

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

The 850W, 1000W and 1200W versions of the Quark do honor their 80Plus Platinum certification with ease, with the 850W showing a little higher overall efficiency than the other two models. The 850W version has an average efficiency of 93% within the nominal load range (20% to 100% of the unit's capacity), while the 1000W and 1200W versions both have an average efficiency of 92.6%. The largest differences occur when the units are heavily loaded, with the 850W version being more stable than the more powerful variations. On the other hand, the 750W version is the least efficient when heavily loaded, with the efficiency dropping down to 90.2% at full load. Still, the average efficiency of the 750W is high, with an average of 92.5% within the nominal load range.

Intake & Exhaust Air Temperature

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

Heatsink Temperature

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

In room temperature, all four of the Quark PSUs displayed the exact same thermal and acoustics behavior. The internal temperatures of every PSU increase very smoothly, almost linearly, with their magnitude being about the same for every unit at a specific load. Ultimately, the more powerful units appear to be warmer just because their maximum output is higher.

In terms of acoustics, the behavior of the cooling system appears to be an exact copy between all of the PSUs, tying the fan's speed only to the relative load of the unit as long as the temperature is low enough. The Quark PSUs are dead silent when lightly loaded, with their fans essentially speeding up after the load has surpassed 60% of the unit's capacity. Even when loaded to the maximum, the SPL is below 36 dB(A), which corresponds to a very soft humming noise.

Sound Pressure Level

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

Hot Test Results

Switching over to our hot testing results, as we see in the following tables, the Rosewill Quark PSUs generally offer very good power quality. The maximum ripple on the 12V lines is below 42 mV under full load, with the 750W version displaying weaker filtering than that of the more advanced platforms. The filtering of the 3.3V/5V voltage lines is very good as well, with our maximum reading being 34 mV when the 1200W version was heavily cross-loaded. Voltage regulation is good, at about 2% for the 850W to 1200W version and about 1.4% for the 750W version of the Quark.

Rosewill Quark 750W - Main Output
Load (Watts)	152.03 W		379.52 W		563.81 W		748.51 W
Load (Percent)	20.27%		50.6%		75.17%		99.8%
	Amperes	Volts	Amperes	Volts	Amperes	Volts	Amperes	Volts
3.3 V	1.98	3.38	4.94	3.36	7.41	3.33	9.88	3.32
5 V	1.98	5.16	4.94	5.13	7.41	5.09	9.88	5.05
12 V	11.13	12.14	27.83	12.13	41.75	12.01	55.67	11.96

Line	Regulation (20% to 100% load)	Voltage Ripple (mV)
		20% Load	50% Load	75% Load	100% Load	CL1 12V	CL2 3.3V + 5V
3.3V	1.6%	12	12	12	14	14	12
5V	2%	14	20	22	22	26	16
12V	1.5%	30	36	36	40	36	42

 

Rosewill Quark 850W - Main Output
Load (Watts)	172.7 W		429.61 W		635.84 W		846.17 W
Load (Percent)	20.32%		50.54%		74.8%		99.55%
	Amperes	Volts	Amperes	Volts	Amperes	Volts	Amperes	Volts
3.3 V	2.27	3.39	5.67	3.36	8.51	3.32	11.35	3.31
5 V	2	5.16	4.99	5.15	7.49	5.08	9.99	5.05
12 V	12.71	12.17	31.78	12.11	47.66	11.95	63.55	11.93

Line	Regulation (20% to 100% load)	Voltage Ripple (mV)
		20% Load	50% Load	75% Load	100% Load	CL1 12V	CL2 3.3V + 5V
3.3V	2.2%	10	12	18	22	20	24
5V	2.3%	10	16	18	26	22	26
12V	2%	16	20	26	36	36	30

 

Rosewill Quark 1000W - Main Output
Load (Watts)	203.05 W		503.92 W		750.6 W		996.17 W
Load (Percent)	20.31%		50.39%		75.06%		99.62%
	Amperes	Volts	Amperes	Volts	Amperes	Volts	Amperes	Volts
3.3 V	2.27	3.39	5.68	3.37	8.52	3.32	11.37	3.31
5 V	2.27	5.16	5.68	5.15	8.52	5.06	11.37	5.05
12 V	15.09	12.17	37.74	12.07	56.6	12	75.47	11.94

Line	Regulation (20% to 100% load)	Voltage Ripple (mV)
		20% Load	50% Load	75% Load	100% Load	CL1 12V	CL2 3.3V + 5V
3.3V	2.4%	12	16	20	22	20	26
5V	2.2%	14	18	20	24	20	28
12V	1.9%	20	22	28	34	36	36

 

Rosewill Quark 1200W - Main Output
Load (Watts)	243.25 W		607.74 W		902.88 W		1196.86 W
Load (Percent)	20.27%		50.65%		75.24%		99.74%
	Amperes	Volts	Amperes	Volts	Amperes	Volts	Amperes	Volts
3.3 V	2.31	3.38	5.79	3.38	8.68	3.33	11.57	3.32
5 V	2.04	5.17	5.09	5.15	7.64	5.07	10.18	5.04
12 V	18.51	12.15	46.29	12.14	69.43	12.03	92.57	11.96

Line	Regulation (20% to 100% load)	Voltage Ripple (mV)
		20% Load	50% Load	75% Load	100% Load	CL1 12V	CL2 3.3V + 5V
3.3V	1.9%	14	18	24	26	24	30
5V	2.4%	16	18	26	30	26	34
12V	1.6%	20	26	34	38	40	32

Once again, we need to mention that these PSUs are rated at 40°C and we perform our testing at temperatures higher than 45°C - we could reduce the ambient temperature of our hotbox testing but we chose not to do so as the results would then not be comparable to those of our previous reviews.

High ambient temperatures have a significant impact on the electrical performance of the Quark PSUs. The average energy efficiency reduction is 2.5%, with the drop being very high when the units are heavily loaded, reaching 4.3% in the case of the fully loaded 750W version. Considering that these are units rated for operation at 40°C, running them at maximum capacity in higher temperatures are overload conditions for the Quark PSUs, which do well enough maintaining reasonable performance and power quality.

Efficiency

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

Power Losses

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

The internal temperatures per % capacity of the Quark PSUs inside the hotbox are nearly identical between the four units, with all four units reaching almost 100°C under full load. There are measurable thermal performance differences between the units, as the actual difference for a specific load is sometimes more than a few temperature degrees. This is especially true between the 750W version and the more powerful units, which are different platforms.

Intake & Exhaust Air Temperature

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

Heatsink Temperature

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

With such high internal temperatures, it was given that the speed of the fans would greatly increase, as the cooling system would strive to maintain operational temperatures within the units. For the 850W to 1200W versions, all three units display a linear increase of the fan's speed as the load increases, with the noise level reaching up to about 50 dB(A) at maximum load. The 1200W is slightly louder than the other two units, with a maximum of nearly 54 dB(A). What surprised us was the acoustics performance of the 750W version, which is greatly inferior to that of the significantly more powerful units. The rate at which the SPL increases significantly higher, with the 750W unit reaching a maximum of nearly 58 dB(A), making it much louder than the more powerful (and different platform) 850W version. As the speed of the fan was not much greater at this point, we can only surmise that the ball bearing fan of the 750W version has a significantly louder engine or that somehow a much stronger aerodynamic drag is being created by the fan or inside the unit. 

Sound Pressure Level

Rosewill Quark 750WRosewill Quark 850WRosewill Quark 1000WRosewill Quark 1200W

Conclusion

The Quark PSU series from Rosewill is an attempt to blend top tier performance with a lucrative price tag, alluring those that care only for raw power, good quality and not much else. Despite this being the best series the company offers, Rosewill is still trying to maintain their company profile and mainly compete in terms of value. To that end, extra features and aesthetic improvements are being dismissed, perhaps to a point that they should not have had. For example, the simple, color-coded modular cables are not common among units of this price range.

As far as quality goes, we would classify the Quark PSUs as "Very High", but it is no secret that we have seen better platforms in the past. Enhance is a reputable OEM that designs very good core platforms and, after seeing the assembly and performance of the Rosewill Quark PSUs, we cannot deny that the 13XX Platinum GT platform is very good. The 13XX Platinum platform that the 750W version is based on leaves nothing to be desired in terms of quality, but the power quality and efficiency fall slightly behind that of the GT version of the platform. We also have to voice our thoughts regarding the selection of internal components. Generally, Rosewill seems to be using very reputable suppliers, but the presence of brands with mediocre reputation (Unicon) troubles us. All of the major components in the samples that we received come from very reputable manufacturers (Matsushita, Panasonic, Nippon Chemi-Con, Nichicon, etc.), yet the erratic mix suggests that Rosewill is using the components of whichever manufacturer is available at the time with products that meet certain specifications. Hopefully, Rosewill will stick to high quality suppliers, at least for the major components. Regardless, all of the Quark series units come with a reassuring five-year warranty.

On the other hand, the overall performance of the Quark series PSUs is very good. They do tend to get hot when heavily stressed inside a very warm environment, but they still operate seamlessly and provide excellent power quality, with minimal voltage ripple and very good regulation for their power output. In terms of power quality and stability, the Quark series units can compare to most of the top tier units and designs of every manufacturer. When the units operate in room temperature, the noise level is very low and, with the exception of the 750W model, it remains reasonable even when the PSUs are very heavily stressed. However, the ball bearing fan, smaller heatsinks and, generally, different platform of the 750W model has a significantly different behavior, maintaining about the same operating temperatures but at the expense of a considerably higher noise level.

Nonetheless, the fundamental issue regarding the Quark series is not concerning the quality or the performance of the units. The quality and overall performance of the Quark PSUs is adequate for their intended market, while the five-year warranty is reassuring. Rosewill however has to compete against other manufacturers in terms of value as well, and the current retail pricing of the Quark series is problematic. With their retail price ranging from $210 for the 1200W model to $130 for the 750W model, some of the Quark PSUs are equally priced to products such as Seasonic's famous SS-1200XP3 ($200) and the Corsair AX760 ($140). Rosewill's current pricing scheme is, at the very least, confusing. For example, either due to stock levels or sales, the 1000W version of the Quark currently retails for $1 less than the 850W model, which is a less powerful design based on the same platform. The low retail price of the 1000W version is alluring, but it is obvious that the pricing of the rest of the units is in dire need of adjustments before the Quark series can have a strong competitive edge in the market.