OCZ ModXstream Pro 500w
Text Config, Voltages, Effiency & Temperatures
Published: 27th January 2009 | Source: OCZ | Price: £49.42 |
Load Configuration
To provide our readers with the most accurate results, Overclock3D uses a professional grade SunMoon SM-268+ ATE load tester capable of placing a sustained load of 1690w across a total of six rails (including +5vsb and -12v) on the PSU. Unlike our previous resistor based load tester the SM-268+ gives us the ability to adjust amperage loads in increments as small as 0.01A while also measuring voltages and wattage readings on-screen.
During todays tests we will be placing the ModXstream under 25%, 50%, 75% and 100% load levels and taking voltage readings at every stage. The chart below details the exact amperage load placed on each rail of the PSU at the aforementioned load levels:
**Total wattage is taken directly from the SM-268+ readout rather than a calculation of the amperage loads.
Results
With testing done at the above settings, we were able to achieve the following results from the ModXstream 500w.
As you can see, the ModXstream 500w has fairly good voltage regulation, with all the voltages well within the ATX specification. The voltages did shift quite a lot as we applied more and more load, with most of them going from small overvolts to a slight undervolt. However, since this is well within the 5% ATX tollerance level, it's nothing to worry about.
Efficiency
Efficiency tests are performed by measuring the wattage consumed by the power supply at the mains (Mains Draw) against the wattage readout displayed on the SM-268+ load tester (PSU Load). These results should offer around 99% accuracy placing them extremely close to results obtained from professional equipment.
Efficiency on the whole was rather good. The 85% achieved between 50-75% is good, but other PSU manufacturers have released models with up to 90% efficiency, so it's nothing ground-breaking. The only minor niggle is the efficiency at 100% load, where it drops to below 83%. However, it is highly unlikely that you will run a PSU that close to its limits, so it shouldn't be a concern the average user.
Temperature
As with all components in the modern computer system, the performance of a PSU can be directly affected by heat. Excess levels of heat recorded at the PSU's exhaust can indicate that the cooling system is inadequate in keeping the PSU's internal temperature under control which can subsequently lead to a reduction in the maximum power output of the unit. For this reason Overclock3D takes temperature readings from the PSU's intake and exhaust areas after 10 minutes of running at each specified load level. These results can be seen below.
The temperature tests didn't give us any readings to be conerned about, with the PSU staying well within comfortable operating temperatures. The 14cm fan obviously does a great job of cooling, and the cool temperature at which the components operate should ensure a long life span.
To provide our readers with the most accurate results, Overclock3D uses a professional grade SunMoon SM-268+ ATE load tester capable of placing a sustained load of 1690w across a total of six rails (including +5vsb and -12v) on the PSU. Unlike our previous resistor based load tester the SM-268+ gives us the ability to adjust amperage loads in increments as small as 0.01A while also measuring voltages and wattage readings on-screen.
During todays tests we will be placing the ModXstream under 25%, 50%, 75% and 100% load levels and taking voltage readings at every stage. The chart below details the exact amperage load placed on each rail of the PSU at the aforementioned load levels:
Input Load | ||||
25% | 50% | 75% | 100% | |
+3.3v | 3.75A | 7.5A | 11.25A | 15.00A |
+5.0v | 3.75A | 7.5A | 11.25A | 15.00A |
+12v1 | 3.75A | 7.5A | 11.25A | 15.00A |
+12v2 | 3.75A | 7.5A | 11.25A | 15.00A |
+5vsb | 0.625A | 1.2A | 1.875A | 2.50A |
-12v | 0.075A | 0.150A | 0.225A | 0.300A |
Total * | 126W | 252W | 376W | 498W |
**Total wattage is taken directly from the SM-268+ readout rather than a calculation of the amperage loads.
Results
With testing done at the above settings, we were able to achieve the following results from the ModXstream 500w.
Output Voltages | ||||
25% | 50% | 75% | 100% | |
+3.3v | 3.37v | 3.34v | 3.30v | 3.26v |
+5.0v | 5.01v | 4.95v | 4.89v | 4.83v |
+12v1 / +12v2 * | 12.14v | 12.05v | 11.95v | 11.85v |
+5vsb | 5.11v | 5.04v | 4.99v | 4.93v |
-12v | -12.02v | -12.11v | -12.21v | -12.31v |
As you can see, the ModXstream 500w has fairly good voltage regulation, with all the voltages well within the ATX specification. The voltages did shift quite a lot as we applied more and more load, with most of them going from small overvolts to a slight undervolt. However, since this is well within the 5% ATX tollerance level, it's nothing to worry about.
Efficiency
Efficiency tests are performed by measuring the wattage consumed by the power supply at the mains (Mains Draw) against the wattage readout displayed on the SM-268+ load tester (PSU Load). These results should offer around 99% accuracy placing them extremely close to results obtained from professional equipment.
Efficiency | ||||
25% | 50% | 75% | 100% | |
Mains Draw | 150w | 296w | 444w | 602w |
PSU Load | 126w | 252w | 376w | 498w |
Efficiency | 84% | 85.1% | 84.6% | 82.7% |
Efficiency on the whole was rather good. The 85% achieved between 50-75% is good, but other PSU manufacturers have released models with up to 90% efficiency, so it's nothing ground-breaking. The only minor niggle is the efficiency at 100% load, where it drops to below 83%. However, it is highly unlikely that you will run a PSU that close to its limits, so it shouldn't be a concern the average user.
Temperature
As with all components in the modern computer system, the performance of a PSU can be directly affected by heat. Excess levels of heat recorded at the PSU's exhaust can indicate that the cooling system is inadequate in keeping the PSU's internal temperature under control which can subsequently lead to a reduction in the maximum power output of the unit. For this reason Overclock3D takes temperature readings from the PSU's intake and exhaust areas after 10 minutes of running at each specified load level. These results can be seen below.
Temperature | ||||
25% | 50% | 75% | 100% | |
Intake | 22.6°C | 23.3°C | 23.6°C | 23.1°C |
Exhaust | 31.45°C | 34.5°C | 36.4°C | 37.8°C |
Delta-T | 8.85°C | 11.2°C | 12.8°C | 14.7°C |
The temperature tests didn't give us any readings to be conerned about, with the PSU staying well within comfortable operating temperatures. The 14cm fan obviously does a great job of cooling, and the cool temperature at which the components operate should ensure a long life span.
Most Recent Comments
Nice review
It's certainly interesting to see another of the OCZ lower budget series, the StealthXstream were already very interesting.
I don't think it can compete with the cooler master m520 when it's about price though. The ModXstream retails for â¬65.- in the Netherlands while me m520 is about â¬7-8 cheaper. May not sound like a lot but most of the time these psu's are used in low budget builds where every penny counts.
I think it would be a good idea to make three PSU roundups. For low (400w-), mid (400-700w) and high (700w+) units. That way it's easy to compare the reviewed supplies
To be continued, have to eat now
Quote

I don't think it can compete with the cooler master m520 when it's about price though. The ModXstream retails for â¬65.- in the Netherlands while me m520 is about â¬7-8 cheaper. May not sound like a lot but most of the time these psu's are used in low budget builds where every penny counts.
I think it would be a good idea to make three PSU roundups. For low (400w-), mid (400-700w) and high (700w+) units. That way it's easy to compare the reviewed supplies

To be continued, have to eat now

This looks really decent, been toying with the idea of going modular when I upgrade my backup rig at easter, and the price had put me off but £50 is a small price to pay for something that performs well and could replace my Corsair in the event of an emergency. Good review, with a nice decisive conclusion
Quote

Quote:
Originally Posted by name='soapsupah'
first, thanks for the review Jim, and now, coments: it looks pretty good for a 500w psu, the temps of it aren't bad, it does it job well, its silent, and isnt expensive at all, maybe this is another one for me to chose? im still having trouble at choosing 500w modular psu's. i think i still have the corsair as my top.
Anyways, great review man ![]() Soap. |
Quote:
Originally Posted by name='monkey7'
I think it would be a good idea to make three PSU roundups. For low (400w-), mid (400-700w) and high (700w+) units. That way it's easy to compare the reviewed supplies
![]() To be continued, have to eat now ![]() |
Once again, nice review and good so see some midrange products

Anyways, great review man
Soap.Quote