Introduction

It seems that manufacturers are really serious on the race for who has the smallest case, and Antec is a serious contender with ISK 300-65, a tiny mini-ITX case that in order to reduce its size to the maximum it uses a laptop-style external 65 W power adapter. Is it worthwhile buying this case? Let’s see.

Measuring only 3 ¾” x 8 ¾” x 12 29/32” (9.6 cm x 22.2 cm x 32.8 cm), this case makes the other two small form factor cases we recently reviewed, SilverStone Sugo SG05 and Sugo SG06, to look like giants, as they have more than double the height. Cutting down the height by less than a half was possible by removing the power supply from the case. ISK 300-65 weights 7.5 lbs (3.4 Kg).

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Figure 1: Antec ISK 300-65 case.

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Figure 2: Antec ISK 300-65 case.

ISK 300-65 has two meshes: one on the top panel, above the area where a slim expansion card can be installed, and one on the right panel, in front of the 80 mm fan that comes with the product. We will talk more about this fan later.

Of course to reduce its size ISK 300-65 only supports slim optical drives, i.e., drives originally developed for portable computers. The only drawback is that this option increases the final cost of your computer, as slim drives are more expensive.

The front panel has a very sober and professional looks. The bay for the slim optical drive is protected by a cover, and ISK 300-65 has one eSATA port and two USB ports, plus the traditional microphone and headphones jacks. The additional of an eSATA port is an obvious plus, but the two USB ports are located too close to each other, preventing you from installing two “fat” USB devices at the same time.

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Figure 3: Front panel.

In Figure 4, you can see the rear panel from the reviewed case. You can see the jack for installing the external power adapter, the three-step speed control for the internal fan (a hole for a second speed control switch is available, as you can optionally install a second fan – more on this later) and one slim expansion slot. Of course you can only install one slim expansion card with this case. Notice how the top cover is fastened to the chassis using thumbscrews, which is great.

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Figure 4: Rear panel.

Inside ISK 300-65

Now let’s take a look inside ISK 300-65. On Figures 5 and 6 you have an overall look from its interior. ISK 300-65 has a DC-DC converter on its bottom front part, in charge of converting the voltage provided by the external power adapter to the required voltages and cables. We will talk more about this converter later.

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Figure 5: Overall look.

It comes with one 80 mm fan on its right side and a second fan can be installed by removing the black plastic cover located on the left-hand side of the fan in Figure 6. This is a “TriCool” fan, providing three different speeds (low, medium and high), configured through the switch available on the rear panel. Since there is a place for installing a second switch on the rear panel the second fan can be an identical “TriCool” fan. No information on the actual speeds, airflow or noise level is available.

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Figure 6: Overall look.

In Figure 7, you can see the case with the top hardware removed. Of course this case will only hold mini-ITX motherboards. Because of its reduced height, it will only support CPU coolers with up to 2 ½” (65 mm) in height.

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Figure 7: Motherboard tray.

The single expansion card supported by this case is fastened to the case using a different mechanism, shown in Figure 8.

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Figure 8: Mechanism to hold the daughter board.

The Disk Drive Bays

This case has one external bay for slim optical drives and two internal 2.5” bay for hard disk drive or SSD units. The two 2.5” bays are located side by side on the front part of the case, on the top of available plate. Drives must be screwed from below and this plate is easily removed by unscrewing one thumbscrew. The slim optical drive bay is located on the compartment below the 2.5” bays.

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Figure 9: The disk drive bays.

The Power Supply

One of the unique features from this case is the presence of a laptop-style 65 W external power adapter (19 V, manufactured by Delta Electronics), as shown in Figure 10. Inside the case there is a DC-DC converter to transform the 19 V DC provided by the power adapter into +12 V, +5 V, +3.3 V, +5VSB and -12 V. Since we have the necessary equipment, we decided to test this power supply to see if it can really deliver 65 W and what is the quality of the outputs (i.e., noise and ripple).

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Figure 10: External 65 W power adapter.

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Figure 11: DC-DC converter.

The cables provided by the DC-DC converter are:

• Main motherboard cable with a 20/24-pin connector, using 20 AWG wires.
• ATX12V cable, using 22 AWG wires on the yellow wires and 20 AWG wires on the black wires.
• SATA power cable, with two SATA connectors, using 20 AWG wires.
• Peripheral power cable, with two standard peripheral power plugs, using 20 AWG wires.

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Figure 12: Cables.

All cables are very short, having only 9 1/16” (23 cm) between the converter and the first connector on the cable and 4” (10 cm) between connectors, as we would expect on such a small case. The wires are thinner than normal, but at only 65 W maximum power they seem to be using the correct gauge.

The Power Supply Tests

For testing the power supply we used the load pattern listed below. If you add all the power listed for each test, you may find a different value than what is posted under “Total” below. Since each output can vary slightly (e.g., the +5 V output working at 5.10 V), the actual total amount of power being delivered is slightly different than the calculated value. On the “Total” row we are using the real amount of power being delivered, as measured by our load tester.

This time we tested the power supply at 25º C. We did like this because the power adapter is located outside the case and also a 65 W power supply does not produce a lot of heat.

Input
+12V1	2 A (24 W)
+12V2	1.8 A (21.6 W)
+5V	1 A (5 W)
+3.3 V	1 A (3.3 W)
+5VSB	1 A (5 W)
-12 V	0.5 A (6 W)
Total	62.6 W
% Max Load	96.3%
Room Temp.	25.8º C
PSU Temp.	26.0º C
Voltage Stability	Pass
Ripple and Noise	Failed on -12 V
AC Power	77.7 W
Efficiency	80.6%
AC Voltage	114.1 V
Power Factor	0.594
Final Result	Pass

The power supply included with Antec ISK300-65 can really deliver 65 W. Efficiency is not spectacular, but is above 80%. All voltages were very stable and close to their nominal values. Ripple and noise were below the maximum allowed all the time, except on -12 V, which was at 178.8 mV (the maximum allowed is 120 mV).

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Figure 13: -12 V output with the power supply delivering 62.6 W (178.8 mV).

Below you can see the outputs during our test. As we always point out, the limits are 120 mV for +12 V and 50 mV for +5 V and +3.3 V and all numbers are peak-to-peak figures.

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Figure 14: +12V1 input from our load tester with the power supply delivering 62.6 W (35.4 mV).

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Figure 15: +12V2 input from our load tester with the power supply delivering 62.6 W (40.6 mV).

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Figure 16: +5 V output with the power supply delivering 62.6 W (14.0 mV).

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Figure 17: +3.3 V output with the power supply delivering 62.6 W (12.4 mV).

Main Specifications

Antec ISK 300-65 case main specs include:

• Style: small form factor (SFF)
• Application: Mini-ITX.
• Material: Zinc-coated steel (SECC).
• Power supply required: 65 W external adapter with internal DC-DC converter.
• Available colors: Black.
• Side panel: Meshed (right panel).
• Dimensions: 3 ¾” x 8 ¾” x 12 29/32” (9.6 cm x 22.2 cm x 32.8 cm)
• Net Weight: 7.5 lbs (3.4 Kg)
• Gross Weight: 8.2 lbs (3.7 Kg)
• Bays: One bay for slim optical drive, two internal 2.5” bays.
• Expansion slots: one (slim, a.k.a. half-height)
• Fans: One 80 mm on right panel.
• Optional fans: One 80 mm on right panel.
• More Information: http://www.antec.com
• Average price in the US*: USD 70.00

* Researched at Newegg.com on the day we published this review.

Conclusions

Antec ISK 300-65 is a small case targeted to users that want to build the smallest PC around. Here is a summary of what we found about this product.

Strong Points

• One of the smallest cases on the market today.
• Two 2.5” hard disk drive bays.
• External power supply (approved on our tests).
• Fan with speed control.
• eSATA port.
• Excellent cost/benefit ratio.

Weak Points

• No anti-vibration mechanisms for the hard disk drives.
• No screwless mechanisms for holding hard disk drives.
• The two USB ports are too close to each other, preventing you from installing two “fat” USB devices at the same time.
• The use of a slim optical drive increases the final cost of the computer.

ISK 300-65 is a good product for users looking for a case for building the smallest PC they can. The use of an external power supply helped to reduce the size of the PC, to lower the acoustic noise level (as this external power adapter doesn’t have a fan) and also to reduce the temperature inside the computer. Costing USD 70 it provides an excellent cost/benefit ratio for users looking for the smallest mini-ITX case around.