Flex + PICO PSU in a system

[gbellman]

Hi all, I'm looking to build my first SFF pc, my setting will be like this:

- Ryzen 5 2600
- Asrock Fatal1ty B450 ITX
- 1x8GB DDR4 3200mHz Corsair LPX
- 1x GTX1060
- 1x 256GB m.2 NVME SSD
- 1x 500GB SATA SSD
- 1x 250GB 7200rpm slim HDD
- 1 x BT keyboard + 1 wireless mouse
- 400-450W flex PSU (gold/platinum rated)

I used outervision.com PSU calculator and they recommended 375W, but I'm getting 400-450W for this setting. And I plan to upgrade to 3700X, 1x1080ti, 2x8GB ram in future when my budget is not as tight, by that time the 400-ish PSU won't be sufficient.

Just wondering by that time if I add a PICO 250W, which will be supplying to mobo+CPU, and the flex PSU will take care of the GPU+SSD+HDD+casing fans, but the PICO 12v DC input will be coming from the flex PSU also, is that possible? Will that reduce the burden of the flex PSU?

Flex PSU |--> PICO --> MOBO+CPU
|
|-> GPU, SSD/HDD, fans, any other component

Thanks

 

[Kilrah]

The load on the Flex PSU would actually be higher.

 

[gbellman]

The load on the Flex PSU would actually be higher.

Oh is it? gosh.... meaning i have to think of other way ?

 

[Choidebu]

I used outervision.com PSU calculator

They're garbage. All of them. 400-450 is heaps. you're probably will only be pulling ~220W off the wall.

- 1 x BT keyboard + 1 wireless mouse

You didn't... count them in... did you?

Just wondering by that time if I add a PICO 250W, which will be supplying to mobo+CPU, and the flex PSU will take care of the GPU+SSD+HDD+casing fans, but the PICO 12v DC input will be coming from the flex PSU also, is that possible? Will that reduce the burden of the flex PSU?

It doesn't work that way. A pico psu doesn't add supply wattage. If it pulls from your flex then obviously it is eating into your flex's wattage. So you still only have 400-450W.

 

[gbellman]

They're garbage. All of them. 400-450 is heaps. you're probably will only be pulling ~220W off the wall.

hmmm..... no matter how i still need to get a 600w psu

 

[gbellman]

You didn't... count them in... did you?

i did included them

It doesn't work that way. A pico psu doesn't add supply wattage. If it pulls from your flex then obviously it is eating into your flex's wattage. So you still only have 400-450W.

then i guess i need to get a 600w psu, since that it'll add more load to the flex psu

 

[paulesko]

No no, you are perfectly fine with a 450 psu or a 400 for that matter. that configuration you propose, (as @Choidebu stated above) is not going to take up more than 250w, probably more like 200, so with 400 you are perfectly fine.

 

[Thehack]

1080 ti uses like 220w for gaming loads. CPU uses like 60W, add 20w for rest of the system and its actually 320w.

450w gold rated flex should handle it though if it is rated accurately. But usually noise becomes a big problem with flex units.

 

[paulesko]

Yes, I was talking about the actual config he said, not the future one. But anyway 400 ish should be enough. Then if you overclock or undervolt all this is not valid

 

[Thehack]

Yes, I was talking about the actual config he said, not the future one. But anyway 400 ish should be enough. Then if you overclock or undervolt all this is not valid

I was reading it as he is taking the 12v for the Pico from the flex.

 

[gbellman]

1080 ti uses like 220w for gaming loads. CPU uses like 60W, add 20w for rest of the system and its actually 320w.

450w gold rated flex should handle it though if it is rated accurately. But usually noise becomes a big problem with flex units.

actually there are 500w & 600w flex psu but they are much more expensive, so i guess i'll go for the 500w, save the worry ?

 

[gbellman]

I was reading it as he is taking the 12v for the Pico from the flex.

yes in case the 450w not enough, cuz i thought the flex will only provide 12v which won't add load to it but that's not the case

 

[gbellman]

Yes, I was talking about the actual config he said, not the future one. But anyway 400 ish should be enough. Then if you overclock or undervolt all this is not valid

no i wont be doing any oc

 

[gbellman]

450w gold rated flex should handle it though if it is rated accurately. But usually noise becomes a big problem with flex units.

yes, i'll be getting the low noise one but unsure how quiet will it be, lol ?

 

[Choidebu]

Yeah do that and forget the pico.

 

[gbellman]

Yeah do that and forget the pico.

i'm thinking to get only a 500w pico instead of the flex, but that should be a bad idea as there's no efficiency rating of the pico, and the brick to power it should be massive, defeating the purpose of trying to trim down size & weight of the system

 

[Choidebu]

All things considered the same, you'll pay more for a brick+pico (we call it dc-dc here) than a flex/tfx/sfx/atx psu solution.

btw you can multi quote and insert all quoted messages at once, saving you from replying to every post. Quoting a highlighted text only is also possible. Try it out.

 

[gbellman]

All things considered the same, you'll pay more for a brick+pico (we call it dc-dc here) than a flex/tfx/sfx/atx psu solution.

yes indeed, but my main intention is to reduce the overall system size

btw you can multi quote and insert all quoted messages at once, saving you from replying to every post. Quoting a highlighted text only is also possible. Try it out.

thanks

 

[Day VReamer]

I use a the 400w AC-DC and DC-ATX units by HDPlex. I have a 2080 Ti and an intel 10600 CPU. The 10600 is 65w, and the GPU is 260 ish watts. I use one M.2 for storage. From the wall the whole load is in the range of 430 watts the HDPlex 400w can go up to 500w peak - but the 430 watt reading from the wall is the max it will roughly allow. If you did want to go to a 1080 Ti later on I would go for 500w as a minimum for the power supply. HDPlex is a good option, but as people have said the combination of the AC-DC unit and the DC-ATX unit will be more expensive at around £180. I also made my own AC-DC brick (which was just an HDPlex 400w AC-DC unit in an enclosure). You can see my build log here: https://smallformfactor.net/forum/threads/non-portable-almost-non-laptop-build.14544/

 

[Teebs]

Another positive reccomendation for the 400w HDPlex combo from me.