FSP has introduced its first FlexATX power supplies, which will be available through retail channels and value added resellers. The FlexGuru PSUs are fully modular and are rated at 250 W and 300 W. Supporting virtually all technologies that one would expect from a modern desktop power supply, FSP’s FlexATX products are aimed at a broad set of applications from industrial PCs to servers and from HTPCs to NAS.

FlexATX power supplies have traditionally been used for small form-factor desktops by large OEMs, as well as for specialized PCs built in large quantities. As demand for miniature computers is on the rise and the market for specialized edge computing systems is set to rapidly grow in the coming years, it's a good time for FSP to roll-out its FlexGuru family of modular PSUs. These PSUs are aimed at smaller PC/server makers, VARs, and even DIY enthusiasts (assuming that the latter can obtain a proper chassis and other components) that do not need high capacity PSUs and require some additional flexibility when it comes to cables.

The FlexGuru PSUs measure 150×40.5×81.5 mm and are compatible with the latest Flex ATX 1.22 specification. FSP says that to guarantee compatibility with 99% of Flex ATX chassis (which feature a different PSU orientation), the FlexGuru power supplies come with a special bracket called ‘Beetle’. The power supplies do not officially conform with any 80 Plus requirements, though FSP itself says that the 250 W version is more than 85% efficient, whereas the 300 W model is more than 90% efficient under typical loads. Meanwhile, like other contemporary power supplies, FSP’s FlexGuru support over power, over/under voltage, over temperature, and short circuit protection technologies

The Flex ATX power supplies from FSP use Japanese electrolytic capacitors and feature a single +12 V rail design. Both PSUs are equipped with a 40-mm ball bearing fan that spins at 3000 ~ 6000 RPM depending on the load, producing 30 ~ 38 dBA noise.

Both FlexGuru PSUs feature a modular design and come with one ATX 20+4 connector, a 4+4 EPS 12v power connector, four SATA power plugs, two Molex power outputs, and two FDD power connectors. To ensure greater flexibility, FSP uses slim ribbon cables.

FSP's FlexGuru Series Output Specifications
  FSP250-50FGBBI(M) FSP300-57FCB
Rated Combined
(max load)
Rated Combined
(max load)
+3.3V 12 A 39.6 W 12 A 39.6 W
+5V 14 A 70 W 14 A 70 W
+12V 18 A 250 W 25 A 300 W
-12V 0.3 A 3.6 W 0.3 A 3.6 W
+5Vsb 3 A 15 W 3 A 15 W
Total Power 250 W 300 W

FSP’s FlexGuru 250 W and 300 W PSUs are already available from Amazon. The 250 W model costs $86.99, whereas the 300 W SKU is priced at $96.99.

Related Reading:

Source: FSP
Image Credit: Amazon

Comments Locked

12 Comments

View All Comments

  • zcat - Friday, August 23, 2019 - link

    Why does a 250W PSU need an 8pin PCIe connector for a video card? If the video card needs more than the 75W that the PCIe slot itself provides, then the rest of the mismatched system is getting very close to starved for power.

    A 250W or 300W PSU should at best be paired with something like a budget 75W Nvidia GTX 1650 or less to leave enough headroom for the rest of the system needs. Who's putting a 180Watt GTX 1070 Ti in a system like this? Even a 120W 1660 is cutting it close.
  • extide - Friday, August 23, 2019 - link

    A 300W PSU could pretty easily run a 150W card with a 95W CPU and be fine.
  • DanNeely - Friday, August 23, 2019 - link

    That's error in the article. It's a 4+4 CPU connector. If you don't trust your common sense, you can go to the linked product page from FSP.
  • Anton Shilov - Friday, August 23, 2019 - link

    Thank you and fixed!
  • SnownedOne - Friday, August 23, 2019 - link

    My Lenovo Idea center Gaming T540 has 310watt Platinum Power supply pushing a i5 9400, 1660ti (6pin), nvme drive, and a sata ssd just fine with sub 250~260 watt draw. Although the staple rule it is better to run things around the 50% mark power to keep them cooler it does just fine and stays in the efficiency sweet range. Ent. stuff runs like 80-95% power 24/7. No stutters or hickups with any game under the sun so thermals and power are fine. Add in blender, streaming, shotcut, browsing you name it and often times a few of those at the same time. Every part runs only about 5~10c warmer than any build I have done liquid cooling a giant heatsink etc and a overpriced case not so whats the point really? Heck I have not even changed out the paste on cpu or gpu yet to a thermal pad or grizzly.
  • evilspoons - Friday, August 23, 2019 - link

    I'd love something like this to cut down on the size of my HTPC (currently has some 450 watt thing that's waaaaay over-specced), except that 40 mm fan looks awfully suspect for making awful high-pitched whining.
  • Lucky Stripes 99 - Sunday, August 25, 2019 - link

    I was thinking the same thing regarding that 40mm fan. I ended up going with an external power brick and a mini-ITX PSU for my latest HTPC build in order to avoid fan noise. There are now a ton of PicoPSU clones on the market, so costs have come down.
  • DanNeely - Friday, August 23, 2019 - link

    This looks to be bogo-modular and designed for looks not actually being very useful. It only has 2 cable bundles. One with the 24pin and 4+4 cpu power connector, any system built will need this but it eats most of the connector space. Then you've got the second connector with 2 sata and 1 molex strings on it. Some systems might not need any of that if they're using an m.2 drive and mobo fan headers. Very few systems this would be going into will need at 3 strings though, and thus if they need any o it will end up with the same mess as a non-modular PSU.

    This really seems like an obvious case for a semi-modular design. Hardwire the 24pin cable (and possibly the CPU 12v one) that every system will need. Put the 3 accessory strings on independent connectors so you only have the wires you need actually connected.

    That or compact the power electronics a tiny bit more and have a second row of modular plugs.
  • Skeptical123 - Saturday, August 24, 2019 - link

    Be careful not to confuse your taste and what a product should be. People overwhelming want full modularity not partial, regardless of how you or I feel. (I'm with you on wanting hardwired 24pin cables in most situations) Also the very nature of this PCU makes it a horrible idea to have a non modular 24 pin cable. As even in SF build the power supple can be vastly different positions and need different cable length. You can hid extra SATA power cords but you can't hid that 1.5 ft long 24pin cable that only need to be 4 inches long in your ITX case. Also don't assume people will a 4+4 EPS 12v power connector. I would argue that connector alone can supply alone more than the power draw of most of the systems these PSU are going to be used in.
  • quorm - Friday, August 23, 2019 - link

    I'd like to see a review.

Log in

Don't have an account? Sign up now