FSP Twins 500W Redundant PSU Review

Pros, Cons, And Final Verdict

We have mixed feelings about the Twins 500W. For starters, we like the idea it's built on. However, the actual implementation could be better with some changes. If FSP provided the option to completely deactivate one module and not use both of them in parallel, then efficiency under light loads would improve significantly. In addition, there would be minimal stress applied to the module in standby, bolstering its reliability. By having both modules operate simultaneously, they endure the rigors of always-on operation, increasing the possibility that they break down at the same time, or at least close together. Given that FSP implemented a digital platform, the right modifications to hardware and software could enable FSP's Guardian app with controls to deactivate this hybrid module operation. Hopefully we see something like this in the family's next revision.

FSP's Twins 500W is an interesting PSU. It's the first server power supply designed to fit in normal ATX cases, addressing enthusiasts who need a highly reliable PSU for their home servers. The build quality is pretty good, and FSP uses top-notch components to ensure the frame and modules enjoy a long lifetime.

The major problem most folks are going to have with the Twins 500W, aside from its steep price tag, is the noise generated by those small fans in the modules. For a server system typically installed in a noisy environment, this doesn't pose a problem. But in a PC that lives in your house, that's a major con. So before you decide to invest in this PSU for a home server, take into account that it will definitely make its presence felt, especially under tough workloads. You'll want to find an isolated space for it. Conversely, if you're adverse to all of that noise, buy a high-quality desktop PSU instead and forget the redundant functionality.

Performance-wise the Twins 500W doesn't set any records, especially when it comes to load regulation and ripple suppression. But we can't forget that it belongs to a special PSU category, so comparisons to normal desktop PSUs are inherently unfair. This is a server-type unit offering increased reliability and a rich feature set attributable to its digital circuit, which facilitates monitoring via software.

We would like to see FSP use more PCIe connectors, ideally four of them, along with additional SATA connectors. You might counter that a server PSU won't be used in a gaming system, so two PCIe connectors are enough. Still, this is a server PSU addressing home users, so you never know where it'll end up. Finally, it would be nice if the next Twins generation also offered some modular cables as well. Meanwhile, we are expecting the second member of this line with increased capacity, the Twins 700W, to hit the market pretty soon.

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  • shrapnel_indie
    Quote:

    Pros

    Full power at 45°C

    Quote:

    All cables are fixed, and because this is a server-like product, its maximum operating temperature for continuous full power delivery is 50°C.



    Please explain to me why these numbers don't seem to match up properly. (THB, I may have missed it.)
    0
  • dstarr3
    I really wonder what a consumer could possibly want this for. What is an ordinary consumer doing that they absolutely cannot risk any downtime whatsoever on their rig?
    1
  • nzalog
    I know freenas can be configured to work faster if you can for sure trust the system from not having RAM errors (covered by ECC) and if you can guarantee there is no unexpected shutdown (covered by dual power and ups). However the reliable power is not really required because a SSD as an SLOG device will cover for it, but then the SSD becomes the bottleneck for writes.
    0
  • firefoxx04
    I build several file servers a month for clients. Low end enough to where pre built solutions are not an option. This power supply would be a good fit but it is useless, imo, without some sort of email alert option. Maybe I missed that?

    When I deploy file servers for clients, I always setup some sort of alert system for raid failures so I can fix the problem. What is the point of redundancy if the user has no idea a problem has occurred? Yes i know that this PSU makes a "loud buzzer noise" but I cant have that either. The user needs to continue to use the system and they cannot if it is screaming 100% of the time.

    Send me an email alert. Its easy to implement.
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  • Rookie_MIB
    One thing I'm curious about - what if one unit does fail? Are they bog-standard replacement parts where you can go and buy a similar hot swap redundant power supply or is the system proprietary. If it's the latter, then I don't see many people lining up for this one...
    3
  • apache_lives
    A PSU is but one part of a "reliable" machine, to me this will not increase up time or do anything of any value, seems more like a "makes me feel better" part.
    0
  • Aris_Mp
    about the first comment, the PSU is certified for up to 50C ambient full power delivery, but I choose to test up to 45C every PSU that passed from my test bench (since I also have to evaluate 40C rated units and I need to keep the same conditions for all).
    1
  • PsiReaper
    A perfect PSU upgrade for my UnRAID box..
    0
  • shrapnel_indie
    Anonymous said:
    about the first comment, the PSU is certified for up to 50C ambient full power delivery, but I choose to test up to 45C every PSU that passed from my test bench (since I also have to evaluate 40C rated units and I need to keep the same conditions for all).


    While I'm glad for that, It's also nice to know if a unit rated at 50°C operation will deliver on its "promise" though. (If you exceed the "promised" rating, like the 40°C rated units @ 45, well, it delivered on its promise and then some.)
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  • Pompompaihn
    Newegg has several server chassis for sale that come WITH redundant 500w+ PSUs for less money than just this power supply. Given that the market is low end commercial/prosumer, and it's not going to be for gaming or HTPC, why wouldn't you just buy the whole thing for cheaper?
    1
  • Matel Onely
    Another issue with this is replacement. My server is up out of the way and a real pain to get to. I'd absolutely do not move it if it is powered on. So to replace the power supply I'd probably power it down anyway.

    what they should really do is one of two things
    1) Design it to fit into a DVD drive bay (or two). That way you can pull the broken power supply from the front which is mostly likely easily accessible. Most ATX towers have multiple DVD bays that end up not being used if they are servers.

    2) The second option, and more expensive solution, would be to design an ATX tower where the power supply sticks out the front. Again for easy access for folks using standard ATX type cases.

    Look in a server room. The power supplies are easy to get to. Of course the server racks are also accessible from either the front or back. But they are made for maintenance. To simplify maintenance for ATX cases, some tweaks will have to happen to really make use of these types of power supplies.
    1
  • dstarr3
    Anonymous said:
    Newegg has several server chassis for sale that come WITH redundant 500w+ PSUs for less money than just this power supply. Given that the market is low end commercial/prosumer, and it's not going to be for gaming or HTPC, why wouldn't you just buy the whole thing for cheaper?


    System building rule #1: If your case comes with a PSU, throw it away immediately, because it WILL be rubbish. Server chassis are no exception.
    0
  • drajitsh
    I also noted the discrepancy in temp
    0
  • drajitsh
    I wonder if it is possible to make an intelligent pass through board for connecting dual power supplies. A lot of full tower cases have space for 2 power supplies and you could use a standard ATX power supply.
    0
  • maxwellmelon
    not truly fail safe " DC-DC converters for the minor rails " are not independent so though they may be reliable then the higher voltage side I have seen plenty of 5 volt regulators fail. if it fails the system fails as though the 12 volt rail has two independent options powering it the lower voltages do not. that is a flaw in good redundancy. i have seen plenty of failures of 5 volt dc-dc converters on tvs boards while the 12 volt generation of the switching power supply was still working correctly/cleanly. would have just been nice to see a true dual power supply.
    0
  • mcgyver2822
    It would have to come with a schematic and parts list to enable repair., because at $400 you will want to keep it a very long time., otherwise no one is going to discard a $400 PSU..
    0
  • I
    Niche market results in price way too high for what it is. Back in the day I just put two full ATX in a full tower case with ORing diodes. Yes you lose a few tenths of a volt, but total cost was only $40 per PSU, $10 for diodes, and I used misc PCB, wire and connectors I had lying around or cannibalized. Granted I can't count those parts as FREE, but I can count them as a heck of a lot less than $310 dollars worth.

    Except for taking up twice the space it was a better setup too because if one PSU failed I could source a standard replacement PSU locally except that I already had a spare. A typical consumer isn't going to have spare $400 PSUs lying around.
    0