Antec NeoHE Modular 550w PSU Page: 1

Over a year ago, Antec released its first attempt at a modular Power Supply into the market - the Neopower 480w. It was a huge success, being one of the only high quality modular PSU's available. It may have been lacking a few features, sleeved cables being one of the biggest, but that didnt deter the avid case modder who was willing to lovingly sleeve every cable in the quest for a tidy PC.

Since then, Antec have gone a bit quiet. 480w is no longer enough power for most people with SLI/Crossfire rigs, and Antec have taken the back bench to manufacturers such as Silverstone, Enermax and OCZ. That is until now....


Antec have never been the kind of company to use funky packaging and advertising to lure the unsuspecting public into buying their products. Instead they rely on their reputation as a high quality PSU manufacturer to draw the consumers in. We can see this tradition continued with the NeoHE packaging below.

Antec Packaging Antec Packaging Back

 Antec Box Open Antec PSU Accessories

The unit itself is protected by two hard cardboard sides, each shaped to match the contours of the unit. To prevent scratches and dust, Antec have placed the unit in a plastic bag sealed with sellotape.

Included in the box, is a european power cable, manual, case screws and a plethora of modular cables which i will talk about in the next few pages.

You may be wondering what the HE stands for? Its High Efficiency - which appears to be the key marketing point in Antecs new line of PSU's. We'll talk about that a little more later on in the review.

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Taken from Antec's Website:

* Highly efficient (up to 85%), one super-silent 80mm fan keeps Neo HE cool; less than 18dBA noise level
* Advanced Cable Management System improves internal airflow and reduces system clutter by allowing you to use only the cables you need.
* Universal Input with Active PFC: Use anywhere in the world without worrying about input voltages; Active PFC improves voltage stability and delivers environmentally-friendlier power.
* Dedicated Power Circuitry: Delivers safer, more reliable output to your system’s delicate components. Includes dedicated voltage outputs, triple +12V output circuits, voltage feedback circuitry, and tighter ±3% regulation for improved system stability.
* ATX12V v2.2 and EPS12V compliant; backward compatible with all ATX12V v2.01 systems. Special 4+4 pin connector allows multi standard compatibility
* Three +12V output circuits provide maximum stable power for the CPU independently of the other peripherals.
* Accurate power rating allows Neo HE to deliver its full rated power, 24 hours a day rated at 50ºC.
* Low-speed 80mm fan delivers whisper-quiet cooling and ensures quiet operation by varying fan speed in response to load and conditions.
* SATA connectors for your Serial ATA drives.
* Industrial grade protection circuitry prevents damage resulting from short circuits (SCP), under voltage protection (UVP), power overloads (OPP), excessive current (OCP) and excessive voltages (OVP).
* Approvals: UL, CUL, CE, CB, FCC Class B, TÜV, CCC, C-tick.
* MTBF: 80,000 hours
* Size: 15cm (W) x 8,6cm (H) x 15cm (D)


With a total of 54a spread across 3 +12v rails, this should be an excellent unit for high end, power hungry systems.

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In theme with all other Antec products, the Neo HE has simplistic, no bling styling. The unit appears to be sprayed in a slightly metalic grey paint, and has a elegant Antec logo stamped into the PSU casing.

Antec PSU Antec PSU Side

Something you don't see much in the most modern incarnations of power supplies is the use of an 80mm fan. Most units nowdays opt for 120mm fans to reduce the noise levels and increase cooling power. If i remember rightly, even the Neo HE's predacessor (the Neopower) was fitted with a 120mm fan.

At this point i find it strange that a power supply labeled 'High Efficiency' would use an 80mm fan, unless of course, the unit is so efficient, it doesnt require much cooling?

Antec PSU Back Antec PSU Modular

Looking around the back of the unit, we can see the meshing that allows for the unit to breathe, along with the modular PSU plugs, of which, at first glance appear to be slighty sparse in comparison with other modular power supplies.

Antec have opted not to make the ATX and P4-12v connectors modular which in my opinion is a good idea. I've found that modular ATX connectors make it harder to route the ATX cables around the back of the motherboard as the cables are spread out rather than being in a big bunch.

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Its good to see that Antec chose to sleve the cables on the Neo HE series. This was a feature that was greatly missed on the previous Neopower series, causing case modders to spend many hours pulling the cables apart and sleeving them to give them a cleaner look.

I did notice that Antec chose not to use cable ties underneath the shrink wrap. This is normally done to prevent the sleeving slipping out from underneath the shrink wrap. To see if this was going to be a problem, i took a pair of pliers to the sleeving and attempted to pull it out. The sleeving would not budge regardless of how much i pulled. Good job Antec..


At a glance, the number of cables and connectors included with this power supply seemed a little thin on the ground compared with other modular power supplies i've used in the past (Tagan Easycon & Silverstone Strider). Lets take a look at exactly what is included..

Cables Cables Cables

Cables Cables Cables

As with most modern Power Supplies, the ATX connector can be split or joined together to form either a 20-Pin or 24-Pin connector. The same goes for the P4-12v connector, which can be split or joined together to form either 4-Pin or an 8-Pin connector.

For the most part, the number of connectors included is pretty standard. I was slightly dissapointed at there only being 6 molex connectors, which would actually be reduced to 5 if you was to use the floppy disk extension cable - especially when you take into consideration that the average PC will use 2 molex's for optical drives, possibly 2 molex's for non-sata drives and then several more connectors for fans and other devices. You also need to take into consideration that the arrangement of molex's on the cables may not suit your system layout, and thus some molex's may go unused.

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Looking Inside

Opening up the casing, and we see why this power supply is so heavy. Mounted atop of the capacitors is two large heatsinks, positioned in such a way as to allow the fan to pull cold air straight through them with minimum resistance.


I'm always on the lookout for adjustable pots in PSU's that pass through OC3D, as these can come in very handy on increasing the voltages if they droop under heavy load. Unfortunately i was unable to find any on the Neo HE, which is a great shame - lets hope they are not needed.


On almost all Power Supplies you are likely to see sheets of clear plastic covering some of the components. This is to ensure that no contact is made between any of the internal components and the outer casing.

I was quite worried to see that a large blob of solder (see picture above), had almost broken its way through the plastic and would have come into contact with the lid of the unit. It's hard to tell what this cable is used for, but first impressions would suggest that it's only carrying 12v, and therefore shouldn't be dangerous.

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The Antec Neo HE is the first unit to pass through the new and improved OC3D PSU Stress Tester. The tester is capable of placing loads on the following rails:

+3.3v - 20a Load
+5.0v - 20a Load
+12v1 - 10a Load
+12v2 - 10a Load
+12v3 - 10a Load
+12v4 - 10a Load
(or 40a on a single +12v rail)

The results are collected from a Mastech MAS-345 Multimeter which logs its readings via RS232 to a PC.

The load voltages will be taken after 15 minutes on the PSU Tester - any longer than this becomes a slight problem as the Stress Tester's Resistors hit around 150°c each (and there's 8 of them!).

3.3v Rail 5v Rail

During the tests, the +3.3v rail was actually bang on 3.33v when idle, and only dipped to 3.26v when under load. However, the 5v rail appeared to suffer quite a large drop in voltage when placed fully under load.

12v1 Rail 12v2 Rail

12v3 Rail

All three +12v rails of the Neo HE were stressed at the same time under a total load of 30a (10a per rail). The results were pretty impressive with all rails managing to stay within 3% of their idle voltages. The lowest rail at 11.74v shouldn't cause any issues for components in your system, but its a shame that adjustable pots are not a feature of this unit as they would certainly come in handy.


Either i'm going deaf or this unit is totally silent! During testing i was forced to place my hand at the back of the unit to see if the fan was pushing air through several times. Only when all of the rails were tested together (total 70a load) did the unit emit a silent whisper.

This is where the 'High Efficiency' of the unit comes in to play. The unit managed to remain cool, and keep the fan speeds low under high load, which means that very little energy was turned into heat during the conversion from AC to DC voltage.

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<script type="text/javascript" src=""></script> Posted 03/05/2006
Author: James Napier (XMS)
Hardware Acquired: Antec UK


If you are looking for a unit capable of powering a monster system whilst staying whisper quiet, then this is the power supply for you. The noise (or lack of it) plain outstounded me, proving that a high end silent system is indeed possible.

I was slightly dissapointed with the voltage drop on the 5v rails, which could cause problems on some systems, but in my opinion most users are highly unlikely to stress the 5v rail as much as i did on the previous pages.

The unit currently retails for £81 at Overclockers which i feel is a fair price for a Power Supply of this calibre, and definitely is a match for the likes of Tagan and Silverstone who are also targeting this end of the market.

- Silence!
- Efficient with low heat output.
- Reasonable voltage stability.
- Sleeved Cables
- Spotless paintwork finish.

- 5v rail voltages low under full load.
- Lack of Molex connectors.
- Lack of modular plugs (unable to connect all cables).


Thank you to Antec for supplying this product for review :)

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