Overclock3D.Net :: Print Page :: PC Power & Cooling Silencer 910W ATX PSU

Introduction

If there was a PSU Hall of Fame, one company that would have more units inside there than anyone else would undoubtedly be PC Power & Cooling. Over the years they have produced some of the best power supplies that money can buy, with models such as the Turbo-Cool and Silencer racking up awards worldwide. It's no wonder then that enthusiasts who demand the best will often accept nothing less that PCP&C.

In May 2008 as many of us will remember, PCP&C was taken under the wing of OCZ Technology in an effort to increase availability and share knowledge. This was certainly a success as PCP&C products can now be purchased in just about every large online retailer in the UK, removing the need to place your purchase state-side and wait for customs to sting you with a nice import tax bill. Some may argue that by bringing PCP&C into the 'mainstream' they lost their "supermodel" status, with even average Joe being able to get his grubby mits on one. But as we've seen many times in the past, competition drives progression, and today we're going to be taking a look at one of PCP&C's latest models, the Silencer 910, to find out just how being in the mainstream for the past year has shaped their products.

Silencer 910
Legendary Silencer performance now in an incredible 910W of continuous clean and stable power. Our Silencer 910 power supply gives you unparalleled PC Power & Cooling performance and reliability along with a unique ultra-quiet cooling design, Quad PCI-Express connectors, classic black finish, and a price that seals the deal.

• 910W Continuous @ 50C (1000W Peak)
• NVIDIA SLI Certified (Up To 2 x GTX295)
• 80+ Silver Certified (88% Efficiency); .99 Active PFC
• Up to 90% (10dB) Less Noise per Watt
• +12VDC @ 74A (Powerful Single Rail)
• Rock-Solid, Super-Clean DC Output
• Quad PCI-E and complete array of connectors
• Automatic Fan Speed Control Circuit
• 5-Year Warranty and Tech Support

Probably one of the most noticeable improvements in the specifications of the Silencer 910 from its predecessors is its improved efficiency levels. Previous models from the Silencer range such as the 750 Quad were certainly no slouches with 83%+ being effortlessly achieved. But as we can see from the specs above PCP&C have managed to push this up to 88% on the Silencer 910 with an 80 Plus Silver certificate to prove it.

Other noteworthy features include the 5-Year Warranty, NVIDIA Certification for up to two GTX295's and 1000w peak power delivery - even at 50ºC, which is something I'll certainly be testing in the OC3D hot-box later on in the review.

Packaging & Appearance

One of my favourite things about the packaging on some of the original PCP&C PSU's was just how rugged and industrial it was. It really felt like you'd just purchased something that only 'professionals' would use inside a power hungry server system rather than something aimed at the home user. However, judging by the images below it would seem that PCP&C have finally been bitten by the retail bug and have decided to dress the Silencer 910 in more consumer friendly attire.

The front of the box keeps things fairly plain and simple with a professional blue and black theme combined with picture of the unit and a few key specifications. Around the back of the box is yet another picture of the unit only this time with its top off and a large pair of heatsinks on show. Several short captions surround the image, most of which are taken from the feature list on PCP&C's website. The list also makes a re-appearance on the sides of the box, with one side representing each of the various features with an image, while the other side of the box simply lists all of the features as bullet points.

Two large slabs of styrofoam encase the unit with an L-shaped cardboard divider hiding the PSU's hard-wired cables and other accessories. Included are only the bare basics to get you up and running (Power Cord + Screws) along with a fairly detailed manual and "Powered By PCP&C" case badge. But hang on, where's my PSU test report! EVERY PCP&C PSU up until this point has come with its own individual Chroma test report....even if most average people dont have a clue what it means!

Moving on to a top-down view PSU its self, we can see the familiar PCP&C specification sticker along with an Nvidia SLI and Serial Number sticker over to the right. I think I'm correct in saying that PC Power & Cooling were one (if not, THE) first manufacturer to put the stickers out of the way at the top of the unit. Maybe because they were too big to fit on the side, or maybe so that enthusiasts didn't have to put up with seeing them whenever they peered inside their windowed cases. Who knows!

At the sides of the unit we have something new - some snazzy (dare I say it.. Corsair'esque) PC Power & Cooling stickers. These add some life to what would have been an otherwise quite bland black box , and will certainly be a welcome addition for those who care about their PSU's looks.

In keeping with all previous PCP&C units, the Silencer 910 features a single 80mm fan at the back of the unit. PCP&C believe this design to be superior to a top-mounted fan design used by most other manufacturers as it does not restrict the vertical space available to components inside the unit such as capacitors and heatsinks. Of course, smaller fans often have to work much harder to keep things cool so it will certainly be interesting to see if PCP&C 's stubbornness to continue using 80mm fans is for good reason when we put the PSU through our tests on page 4.

For the moment though, let's check out the cables and internal components over on the next page.

Cables & Connectors

PC Power & Cooling employee's can often be seen clutching crucifixes and mumbling sacred words when they find themselves too close to a PSU with modular connectors. "It's just not right, your cables shouldn't just pull off like that!" they exclaim. Unfortunately for PCP&C though, modular PSU's are very much the 'in' thing at the moment with most enthusiasts not even willing to consider a PSU with hard-wired cables. You only need to look at our recent poll in which over 75% of 2100 voters said they'd only consider a modular PSU as their next purchase to see that PCP&C really are catering for the underdog here....In the retail sector at least.

And here's the bundle of cables now. As we can see you do really get quite a lot of cables with the Silencer 910, which of course is a good thing if you intend on putting the 910w of power to full use. Each and every cable is sleeved in a black mesh right to the tip and finished of with black heat shrink. Even the small amount of wire between each of the connectors on the Molex and SATA plugs is sleeved to perfection. Good job PCP&C.

PCP&C Silencer 910 Connectors
ATX Connector	Native	1x 20+4 Pin
EPS-12v / P4-12v Connector(s)	Native	1x 4+4 Pin, 1x 8-Pin
Molex Connectors	Modular	7x
Floppy Disk Connectors	Modular	1x
SATA Connectors	Modular	12x
PCI-E Connectors	Native / Modular	2x 6+2 Pin / 2x 6+2 Pin

But wait, maybe I've been deceived by the Silencer's large bundle! According to the chart above you get a total of 4x PCI-E cables, 12x SATA Cables and 7x Molex cables. This is significantly less than the likes of Corsair's recently reviewed HX850W, which weighed in with a total of 6x PCI-E, 12x SATA and 12x Molex. In fact, in it's current form the Silencer 910 has the balance of Molex-to-SATA connectors completely the wrong way round for the average enthusiast who will more than likely require no more than four SATA connectors, but possibly more than seven Molex connectors.

The ATX connector is of the 20+4 Pin variety meaning that a block of four pins can be snapped off the end of the connector to reduce it down to the older 20-Pin standards. Two EPS-12v connectors are also provided, one which can be snapped in half to support the 4-Pin P4-12v standard while the other is native 8-Pin. Similarly, two of the four PCI-E connectors can be switched between 6/8-Pin standards by use of an additional 2-Pin connector for supporting high-end graphics cards.

As a side-note, PCP&C you need to make up your mind if you're going to use white or black connectors. Black would be my preference - white is so 90's!

Internal Components

Moving on to the internals of the Silencer 910, the OEM is instantly recognisable as Seasonic with some slight similarities to the X900 reviewed back in 2007. Two large aluminium heatsinks span the length of the unit with horizontal fins designed to make maximum use of the air being pushed through the casing by the 80mm fan. All cables are neatly bunched together and there are some quite large voids inside the unit which will undoubtedly assist with cooling.

PCP&C Silencer 910 Transformer - Yellow thing in disguise

Buried beneath the heatsinks are the two main transformers inside the Silencer 910. The smaller of the two will more than likely be responsible for powering the 5VSB rail which is used primarily for USB devices and also for certain motherboard functions while the PC is in standby mode or indeed powered off. Whereas the larger of the two will have the sole responsibility of providing 12VDC which can then be stepped down via other DC-DC circuitry for poweing the +3.3v and +5v rails.

It looks like I caught quite a lucky break with ID'ing the primary capacitors as if it wasn't for the markings just about visible on the folded part of the jacket, I'd probably be forced to get the soldering iron out. Japanese manufactured Nippon-Chemicon's is the name of the game with specs of 400v / 330uF / 105°C. Similarly over on the secondary side more Nippon-Chemicon KZE's can be spotted. This time with specs of 16v / 2200uF. All good so far.

Lastly we come to the 80mm fan manufactured by ADDA. This is the same fan used inside both the PCP&C Silencer 750w Crossfire Edition and the Silencer S75EPS tested back in 2006. Some things never change eh? The spes of the fan can be seen below:

• Model: AD0812UB-A71GL
• Size (mm): 80x80x25
• Bearing: BALL
• Speed (RPM): 3900
• Airflow (CFM): 50.0
• Noise (dBA): 41.0

Ok, so now we've got all of that out the way let's move on to the testing and see how the Silencer 910 performs at the hands of our updated load testing equipment.

Simulated Load Testing

To provide accurate and consistent results in all of our PSU testing, Overclock3D uses professional grade DC electronic load equipment capable of placing a sustained load of 3690w across a total of six rails (including +5vsb and -12v) on the PSU! This is achieved by using a combination of SunMoon and Analogic electronic load equipment which allow us to adjust amperage loads in increments as small as 0.01A while also measuring voltage and wattage readings on-screen.

During today's tests, we will be placing the PC Power & Cooling Silencer 910 under 25%, 50%, 75% and 100% load levels at both room temperature and inside a hot box regulated to a temperature of around 50°C. Additional 'Cross Load' and a 'Max Load' tests will also be performed under these conditions to simulate how the PSU reacts to heavily uneven loads as well as running above its specified output.

PCP&C Silencer 910W @ Room Temperature
	+3.3v	+5.0v	+12v	+5vSB	-12v	AC Watts / DC Watts	Efficiency	Intake / Exhaust	Δ Temp
Test 1 (Low)	4.37A	4.37A	15.00A	0.75A	0.20A	257w / 227w	88.32%	26.4°C / 33.6°C	7.2°C
	3.40v	5.13v	12.29v	5.11v	-12.24v
Test 2 (Med)	8.75A	8.75A	30.00A	1.5A	0.40A	497w / 454w	91.34%	28.7°C / 40.7°C	12.0°C
	3.39v	5.12v	12.25v	5.07v	-12.27v
Test 3 (High)	13.12A	13.12A	45.00A	2.25A	0.60A	741w / 679w	91.63%	28.4C / 42.3°C	13.9°C
	3.38v	5.10v	12.20v	5.03v	-12.33v
Test 4 (Full)	17.50A	17.50A	60.00A	3.00A	0.80A	1003w / 903w	90.02%	28.0°C / 42.5°C	14.5°C
	3.37v	5.09v	12.16v	4.99v	-12.34v
Test 5 (x-load)	17.50A	17.50A	1.00A	0.00A	0.00A	194w / 160w	82.47%	26.2°C / 32.1°C	5.9 °C
	3.38v	5.10v	12.29v	5.13v	-12.71v
Test 6 (x-load)	1.00A	1.00A	76.60A	0.00A	0.00A	1036w / 911w	87.93%	27.3°C / 41.8°C	14.5°C
	3.39v	5.13v	12.16v	5.10v	-14.47v
Test 7 (MAX)	20.00A	20.00A	75.12A	4.50A	0.60A	1201w / 1084w	86.03%	27.8°C / 46.4°C	18.6°C
	3.37v	5.08v	12.12v	4.93v	-12.39v

The Silencer 910 gets off to a good start with a show of solid voltage stability during the standard load tests(1-4) across all rails. If I wanted to be picky I could say that it would have been nice for PCP&C to set the idle voltages a tad lower as 3.40v and 12.29v is beginning to push on the 'high' side - even though it is of course WELL within ATX specs. The cross-load tests (5 & 6) are also handled reasonably well with the only worrying output being the -12v rail. ATX specs give this rail a tollerance level of ±10%, but in test 6 this manages to hit -14.47v obviously falling well outside of spec. However, as I've said many times before, these cross-load scenario's are highly unlikely to be seen in normal usage so this really isn't so much of a problem.

Efficiency is also very good across the board with the unit managing between 88-90% in all of the standard tests and anything from 82% to 87% in our custom cross-load and max load tests. This obviously helps to keep temperatures inside the unit at manageable levels (with less energy being wasted as heat) and in most cases the delta between Intake and Exhaust temperatures rarely exceeds 14°C.

PCP&C Silencer 910W @ 50c
	+3.3v	+5.0v	+12v	+5vSB	-12v	AC Watts / DC Watts	Efficiency	Intake / Exhaust	Δ Temp
Test 1 (Low)	4.37A	4.37A	15.00A	0.75A	0.20A	257w / 227w	88.32%	52.0°C / 58.1°C	6.1°C
	3.40v	5.13v	12.29v	5.10v	-12.24v
Test 2 (Med)	8.75A	8.75A	30.00A	1.5A	0.40A	500w / 454w	90.80%	51.6°C / 57.8°C	6.2°C
	3.39v	5.12v	12.25v	5.07v	-12.27v
Test 3 (High)	13.12A	13.12A	45.00A	2.25A	0.60A	752w / 679w	90.29%	51.8C / 58.8°C	7.0°C
	3.38v	5.10v	12.19v	5.02v	-12.34v
Test 4 (Full)	17.50A	17.50A	60.00A	3.00A	0.80A	1007w / 899w	89.27%	51.1°C / 65.9°C	14.8°C
	3.37v	5.09v	12.16v	4.98v	-12.45v
Test 5 (x-load)	17.50A	17.50A	1.00A	0.00A	0.00A	196w / 160w	81.63%	52.3°C / 58.4°C	6.1 °C
	3.39v	5.10v	12.29v	5.13v	-12.72v
Test 6 (x-load)	1.00A	1.00A	76.60A	0.00A	0.00A	1052w / 911w	86.59%	51.7°C / 68.3°C	16.6°C
	3.39v	5.13v	12.16v	5.10v	-14.47v
Test 7 (MAX)	20.00A	20.00A	75.12A	4.50A	0.60A	1273w / 1093w	85.86%	52.8°C / 74°C	21.2°C
	3.37v	5.08v	12.08v	4.91v	-12.41v

Re-running the tests again, only this time with an ambient temperature of 50°C really put the cooling inside the Silencer to the test. Normally I wouldn't comment on the noise output of the unit as the load testing equipment is kitted out with numerous large 240v fans that can easily drown out the sound of Metallica playing live in the next room. However, in tests 4, 6 and 7 the 'Silencer' ramped up the fan speed so much that it was clearly audible above the load testers. Silent? I think not.

Aside from the noise, very little changed in any of the other departments. Efficiency dropped by an average of 1% across the board and voltages dropped by 0.01-0.02v. So it's quite clear to see that the Silencer is well equipped for delivering its full 910w load (and above) in the Sahara desert if needed.

One final thing to note before I move on is just how powerful that 12v rail is. Although not an official test I pushed the rail as far as it would go before the PSU powered down. 90A was the magic number. Impressive indeed.

PCP&C Silencer 910w Scope Results @ 50°C
	+3.3v	+5.0v	+12v
Test 1 (Low)
Test 2 (Med)
Test 3 (High)
Test 4 (Full)
Test 5 (x-load)
Test 6 (x-load)
Test 7 (MAX)

For the last part of the testing I analysed the ripple on the +3.3, +5 and +12v rails using a Rigol 25Mhz 400MSa/s oscilloscope. All readings were taken while the Silencer 910 was installed inside the 50°C hot box to provide us with worst case scenario results.

And here are some interesting results indeed! Keeping in mind that ATX spec states that DC output noise/ripple should remain below 50mV(pp) on the +3.3v / +5v rails and below 120mV(pp) on the +12v rail it's not long at all before the Silencer 910 falls outside of specification. By test 3 the +3.3v rail is at 62mV and the +5v rail at 74mV with the +12v rail just about managing to say inside spec at 104mV. When running at a full 911w load in test 4 the +12v rail also goes outside of spec hitting 146mV with the other rails also increasing significantly too.

This is not what I was expecting from PCP&C at all. Convinced something else was amiss somewhere else in the test setup, I swapped out the Silencer with another PSU tested earlier in the week to see if the results differed from the original ones. They didn't. OK so it's not the load testing equipment, maybe its a faulty cable on the Silencer? Nope. As far as I could see, all cables and connectors appeared to be fine and connected well to the load tester.

So who knows. I refuse to believe that these are the actual results having seen much cleaner results from JonnyGuru. But then again these occasional spikes which are bumping up the Vpp results up might not be something that every scope will pick up on. I've asked PCP&C for some insight but as yet have not received a response. Faulty PSU, faulty results, interference from alien life forms. Who knows.

Conclusion

If PC Power and Cooling set out to produce a PSU that delivered excellent levels of efficiency and voltage stability above all else, then (aside from the questionable ripple results) this is something they have certainly achieved. In all of the standard tests the Silencer 910 produced solid voltage outputs and even when placed under a load of 1085w in the 'Max Load' test it still refused to falter. Only in the cross-load results did the -12v rail get a little unruly with the voltage going off the scale to down to -14.47v.

However, when reviewing a product here on Overclock3D we have to take into consideration the results of all similar products we've tested before it and how they performed in all areas. As a result the PC Power & Cooling Silencer 910 is up against some extremely stiff competition with both the Corsair HX850W and Enermax Revolution85+ being tested only a few weeks back.

As much as it pains me to say this (because I'm going to get mobbed by PCP&C fans), the Silencer 910 just doesn't cut the mustard. Sure it's got stable rails and great efficiency, but it simply can't compete with the Enermax and Corsair PSU's when it comes to aspects such as noise levels under heavy load, features and general appearance. The theory about hard wired vs modular connectors simply doesn't carry any weight any more and the 80mm fan layout cherished by PCP&C for such a long time really only works in in server environments where low-profile rackmount cases don't work with a top-mounted 120mm+ fan. If it didn't seem like PCP&C were trying to muscle in on the retail market with fancy new packaging and cosmetic improvements to the 910, then maybe I could be a bit more forgiving and evaluate it as an industrial product, but from where I'm standing at least, it doesn't seem to be the case.

The Good

- Stable voltages across all rails at all loads.

- Managed to maintain the stable voltages even at 1084w!

- Excellent efficiency across all loads.

- Improved packaging (thought it doesn't look "industrial" any more).

The Mediocre

- Only four PCI-E Connectors. Most manufacturers have moved to six for high-output models.

- The Molex conspiracy strikes again. Twelve SATA and only seven Molex connectors!

- Mixture of white and black connectors. *removes M.J pun*. Please make up your mind PCP&C.

The Bad

- Running this PSU above 75% load will more than likely damage your ear drums.

- Weird ripple results. Possibly a faulty unit or some other weirdness. But this stays here until resolved.

- The -12v rail fell outside ATX spec in cross-load results.

Thanks to PC Power & Cooling for sending the Silencer 910 in for review. Discuss this review in our forums.

PCP&C Silencer 910 Rail Layout
DC Output	+3.3V	+5V	+12V1	+12V2	+12V3	+12V4	+12V5	+12V6	-12V	+5VSB
DC Output	24A	30A	74A	-	-	-	-	-	0.8A	3A
Max Power	150W		888W						9.6W	15W
Max Power	910W (1000W Peak)