Seasonic G-Series 450W PSU Review

Seasonic's G series consists of reliable, high-performance PSUs. Today, we're reviewing the G-450 with 450W capacity, which features a semi-modular cabling design.

By Aris Mpitziopoulos
published

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Cross-Load Tests And Infrared Images

Our cross-load tests are described in detail here.

To generate the following charts, we set our loaders to auto mode through our custom-made software before trying more than 1500 possible load combinations with the +12V, 5V and 3.3V rails. The load regulation deviations in each of the charts below were calculated by taking the nominal values of the rails (12V, 5V and 3.3V) as point zero.

Load Regulation Charts

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Efficiency Chart

For the most part, efficiency is between 85 and 90 percent. Only for a small region with typical loads does it manage to go above 90 percent. With 230VAC, efficiency will be notably higher, of course, especially at higher loads.

Ripple Charts

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Infrared Images

Toward the end of the cross-load tests, we took some photos of the PSU with our modified FLIR E4 camera that delivers 320x240 IR resolution (76,800 pixels).

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As you can see from the above thermal images, we really stressed the PSU inside the hotbox, and despite the hard conditions, it managed to operate flawlessly.

Aris Mpitziopoulos
Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.

18 Comments Comment from the forums
  • InvalidError
    0.4 ohm Rdson is not that bad for primary-side FETs where switching losses tend to be much worse than on-losses.

    Also, FETs with better on-resistance usually have larger gate charge, which means you end up needing more gate drive power to achieve the same switching performance. Saving 3W on full-load on-losses does not sound as good if it costs you 2W in gate drive regardless of load.

    Using FETs with lower on-resistance does not necessarily improve overall efficiency by much.
    Reply
  • TechyInAZ
    Good read. I personally have the 550W version of that PSU and it works very well. Very quiet too, however my entire system doesn't go beyond 350W at max load.

    BTW...The 550W version is usually only $3-$5 more than the 450W. I've never seen the price change either, so it is a bit silly to buy the 450W version if the 550W is always only $5 more.
    Reply
  • Dunlop0078
    I also have the 550watt version, its been going strong for about two years now its very quiet even under load I think I pull about 450watts or so when I have all my overclocks applied. It has been totally stable not a single problem with my PC or the psu since I bought it.

    However I think the price should be lowered a bit for the 550watt version because now it has to compete with the likes of the EVGA 550 G2 which is about the same price but it seems to perform a bit better and comes with a 10 year warranty.
    Reply
  • TechyInAZ
    16760449 said:
    I also have the 550watt version, its been going strong for about two years now its very quiet even under load I think I pull about 450watts or so when I have all my overclocks applied. It has been totally stable not a single problem with my PC or the psu since I bought it.

    However I think the price should be lowered a bit for the 550watt version because now it has to compete with the likes of the EVGA 550 G2 which is about the same price but it seems to perform a bit better and comes with a 10 year warranty.

    10 year warranty!!?? I've been using EVGA graphics cards for years now, I think ill start buying EVGA PSUs now. :D
    Reply
  • Dunlop0078
    16760449 said:
    I also have the 550watt version, its been going strong for about two years now its very quiet even under load I think I pull about 450watts or so when I have all my overclocks applied. It has been totally stable not a single problem with my PC or the psu since I bought it.

    However I think the price should be lowered a bit for the 550watt version because now it has to compete with the likes of the EVGA 550 G2 which is about the same price but it seems to perform a bit better and comes with a 10 year warranty.

    10 year warranty!!?? I've been using EVGA graphics cards for years now, I think ill start buying EVGA PSUs now. :D

    Actually im wrong on that its a 7 year warranty for the 550watt model (still very good in my opinion) the 750watt g2 and above have the 10 year.
    Reply
  • 10tacle
    I know Seasonic is good and an OEM to PSUs for Corsair and whatnot, but I was an unlucky one. My 620W S12II crapped out on an older backup rig after about a year of light use, maybe 250 hours. Unfortunately I voided the 5-year warranty when I had to break the screw seal and open it to get a screw out that accidentally fell in (PC was unplugged when that happened). I figured I'd never need to worry about dealing with a warranty RMA anyway since in nearly 20 years of PC building I've never had one die early on me. WRONG.
    Reply
  • InvalidError
    16760681 said:
    I figured I'd never need to worry about dealing with a warranty RMA anyway since in nearly 20 years of PC building I've never had one die early on me. WRONG.
    Murphy strikes again!
    Reply
  • Blueberries
    This PSU isn't bad but I don't see why anyone would want to pay in the $70's for it when there are gold-- almost platinum rated Leadex PSUs for $80-$90.

    The build quality is what I've come to expect from SeaSonic. Very well built with mostly Nippon Chemi-Con capacitors. Rubycon is also a good brand, and I like to see Infineon MOSFETs in PSUs. This PSU should last forever but isn't very efficient compared to similarly-priced competition.
    Reply
  • turkey3_scratch
    16760497 said:
    16760449 said:
    I also have the 550watt version, its been going strong for about two years now its very quiet even under load I think I pull about 450watts or so when I have all my overclocks applied. It has been totally stable not a single problem with my PC or the psu since I bought it.

    However I think the price should be lowered a bit for the 550watt version because now it has to compete with the likes of the EVGA 550 G2 which is about the same price but it seems to perform a bit better and comes with a 10 year warranty.

    10 year warranty!!?? I've been using EVGA graphics cards for years now, I think ill start buying EVGA PSUs now. :D

    Yeah, aside from the fantastic quality, that was another reason I purchased the G2 over any other PSU.
    Reply
  • tsnor
    "... Seasonic doesn't use a fully modular design in its G series to keep production costs low. Of course, it would be nice if the company changed its strategy and went all-modular on its G-series models since many competing PSUs are, in fact, fully modular...."

    Or maybe they
    (1) know that people will always use the permanent cables that power the MB
    (2) know that two less connectors is a good thing for product reliability
    (3) want to ship a product for people like me that prefer this configuration to a fully modular configuration
    Reply