Corsair RM850x V2 PSU Review: Smaller And Quieter!

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EMC Pre-Compliance Testing

EMC, EMI & EMS Acronyms

Electromagnetic Compatibility (EMC): The ability of a device to operate properly in its environment without disrupting the operation of other close-by devices.

Electromagnetic Interference (EMI): This represents the electromagnetic energy a device emits, which can cause problems in other close-by devices if it is too high.

Electromagnetic Immunity (EMS): Tolerance to electromagnetic emissions.

Equipment & Standards

To properly measure the EMI that a device emits, you need special equipment defined by the CISPR 16-1-1 specification. To learn more about our EMI testing equipment, please check out How We Test Power Supply Units.

In order to minimize EMI noise, some standards have been established. The corresponding standards for Information Technology products are CISPR 32 and its derivative EN 55032. In the EU, every product featuring the "CE" marking has to comply with EN 55032. Both CISPR 32 and EN 55032 divide devices into two classes, A and B. B-class equipment is for domestic environments, so its allowed EMI emissions are significantly lower than for A-class devices.

Swipe to scroll horizontally
CISPR 32 / EN55032 Limits
CISRP 32/ EN 55032 Class A Conducted EMI Limit
Frequency of Emission (MHz)Conducted Limit (dBuV)
Quasi-peakAverage
0.15 - 0.507966
0.50 - 30.07360
CISPR 32/ EN 55032 Class B Conducted EMI Limit
Frequency of Emission (MHz)Conducted Limit (dBuV)
Quasi-peakAverage
0.15 - 0.5066 - 5656 - 46
0.50 - 5.005646
5.00 - 30.006050

EMI Results - Average Detector

The PSU's EMI filter easily passes this test.

EMI Results - Peak Detector

As expected, we don't see any problems with peak detector selected.

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Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.

  • parkerygc8
    Sweet, first review of this I've seen. Thanks.
    Reply
  • leclod
    I didn't go into detail, but I wonder what's the use of that Gold PSU when there's a Seasonic Focus Plus Platinum 750 for a similar price ?
    Reply
  • Aris_Mp
    Gold, Platinum, it doesn't really matter at this efficiency point. What matters the most, in my opinion at least, is noise output now besides the basic (reliability and overall performance).
    Reply
  • powernod
    At last some scoring at the review conclusion!! I always considered the lack of score as Tom's greater weakness about their reviews !!
    Reply