[SOLVED] Is it possible to power a SFF computer with a standard ATX PSU outside the case?

[tomreedtoon]

I'm interested in upgrading Dell Optiplex computers for gaming, video editing and just plain fast purposes. With mini-tower formats, it's easy to switch to a larger ATX supply (usually with adapter cables). But the Small Form Factor models are more plentiful, and they use proprietary PSU's with no upgrades available.

Has anyone tried to run long cables from an ATX supply in a case outside the computer, into an SFF computer? I'm thinking specifically of the Optiplex 9020 models. The 9020 needs an adapter to go from the ATX multi-cable to an 8-pin cable, and just extending those cables into the SFF case would require fewer wires. And obviously I'd mount a cooling fan or three in place of the missing PSU's fan to cool the case.

Would there be any RF interference problems to the computer, or to the outside world's devices like radios and TV's, from the foot-long cable runs? I'm asking this the hope of making these quasi-orphaned SFF computers more useful. Thanks for the advice!

 

[jadenwoolworth]

If you have the right connectors and the cables can reach inside the computer you should be all good. I'm no professional, so I can't tell you for sure about interference, but I don't think the psu does much communication with the computer, if any. Also, I have run many setups in the open with no case and it has not caused issues.

 

[jonnyguru]

i live in the UK and my max budget is 100 pounds

I'm interested in upgrading Dell Optiplex computers for gaming, video editing and just plain fast purposes. With mini-tower formats, it's easy to switch to a larger ATX supply (usually with adapter cables). But the Small Form Factor models are more plentiful, and they use proprietary PSU's with no upgrades available.

Has anyone tried to run long cables from an ATX supply in a case outside the computer, into an SFF computer? I'm thinking specifically of the Optiplex 9020 models. The 9020 needs an adapter to go from the ATX multi-cable to an 8-pin cable, and just extending those cables into the SFF case would require fewer wires. And obviously I'd mount a cooling fan or three in place of the missing PSU's fan to cool the case.

Would there be any RF interference problems to the computer, or to the outside world's devices like radios and TV's, from the foot-long cable runs? I'm asking this the hope of making these quasi-orphaned SFF computers more useful. Thanks for the advice!

If you have the right connectors and the cables can reach inside the computer you should be all good. I'm no professional, so I can't tell you for sure about interference, but I don't think the psu does much communication with the computer, if any. Also, I have run many setups in the open with no case and it has not caused issues.

Yeah. Optiplex 9020 doesn't have standard power connectors. So not only are you going to have this janky PSU outside the case, but you're going to need an adapter. It's going to look and work like ass.

Best thing to do is buy a new case, PSU and motherboard. If you make sure the motherboard supports the CPU and RAM you're using today, it shouldn't be too expensive.

 

[tomreedtoon]

Yeah. Optiplex 9020 doesn't have standard power connectors. So not only are you going to have this janky PSU outside the case, but you're going to need an adapter. It's going to look and work like ass.

Best thing to do is buy a new case, PSU and motherboard. If you make sure the motherboard supports the CPU and RAM you're using today, it shouldn't be too expensive.

Well, I wasn't thinking that "working like ass" would be bad. It is a desktop, not a laptop, and it's gonna stay where I locate it and not move, hopefully for a decade. I know about the 8 pin converter cable, and what I'd do is lengthen the wires to it. I was asking about interference because if necessary, I might find some thick braid shield and shove the wires through that, then run it into the case. I know switching power supplies generate RF, which is why they're in metal boxes, but I was wondering if having bare cables might introduce RF into the environment. Cable companies and emergency services don't like having RF noise that would interfere with cable, or police or fire radios.

I don't want to waste a case I bought, just because Dell was stupid enough to put a good computer in a teeny useless case. Heck, I could get a project box, mount the PSU in it, and bolt the thing to the back or side of the case.

If anyone has actually tried this, and has experience with the mod, I'd appreciate hearing about their experiences with this.

 

[jonnyguru]

Well, I wasn't thinking that "working like ass" would be bad. It is a desktop, not a laptop, and it's gonna stay where I locate it and not move, hopefully for a decade. I know about the 8 pin converter cable, and what I'd do is lengthen the wires to it. I was asking about interference because if necessary, I might find some thick braid shield and shove the wires through that, then run it into the case. I know switching power supplies generate RF, which is why they're in metal boxes, but I was wondering if having bare cables might introduce RF into the environment. Cable companies and emergency services don't like having RF noise that would interfere with cable, or police or fire radios.

I don't want to waste a case I bought, just because Dell was stupid enough to put a good computer in a teeny useless case. Heck, I could get a project box, mount the PSU in it, and bolt the thing to the back or side of the case.

If anyone has actually tried this, and has experience with the mod, I'd appreciate hearing about their experiences with this.

Good to know you know about the converter cable and don't care if it looks bad. Not my thing, but who am I to judge. ;-)

So, as long as the PSU is inside it's case, you're not emitting enough RF and EMI for anyone to care. RF and EMI are also not transmitting down the DC wires into open air either. So I wouldn't worry about that.

To let you know how common it is to have your PSU sitting out in the open with DC cables all over the place:

https://www.amazon.com/Universal-Desktop-Computer-Motherboard-Switch/dp/B07K9P224L
https://www.amazon.com/Bench-Motherboard-Aluminum-Acrylic-Computer/dp/B07MYVMWVJ
https://www.amazon.com/Computer-Cooling-Overclock-Aluminum-Graphics/dp/B07R4X9BZG

Even my own daughter's PC uses this case (because she liked being able to "see" everything:

https://www.amazon.com/InWin-Mini-Black-Motorcycle-Computer/dp/B00PGAEPMI

At work we have about a couple dozen of these: http://shopusa.dimastech.com/bench-test-table-easyxl

So, no. Having your PSU outside of your case is not a big deal.

I will suggest this: Just find some way to ground your Dell chassis to the PSU housing. Like with a ground jumper wire or something. A PC gets it's earth ground through the contact of the chassis and PSU housing being screwed together, as the Earth ground is obviously in the PSU's AC plug. Without that, your only ground is through the DC cables and that's just not "safe enough".

 

[tomreedtoon]

I've abbreviated your quote.

Good to know you know about the converter cable and don't care if it looks bad. Not my thing, but who am I to judge. ;-)

So, as long as the PSU is inside it's case, you're not emitting enough RF and EMI for anyone to care. RF and EMI are also not transmitting down the DC wires into open air either. So I wouldn't worry about that.

Thanks. As a guy who was a TV enginer for 32 years, I understand about grounding. (For audio and video, grounding to the outlet ground isn't enough; we ran copper busbar throughout the plant, under all the racks, all grounded to a huge stake in the earth.)

I'm upset that to get the desired Mini-Tower for a PC I want to u pgrade (the Dell Optiplex 9020) I have to pay a premium because all the build videos on YouTube talk about it. Either you (a) pay for the Mini-Tower and the PSU or (b) live with the miniscule and peculiar supplies Dell builds in, and use an inferior low-power GPU. I'm not interested in gaming or showing off; I want a fast quad core that will render edited videos fast. And I don't need Christmas lights or animated Mickey Mouse robots on the case to show it off.

If I do this, I will document the whole process, record it, put it on YouTube and tell the price pirates to walk the plank. Thanks!

 

[jonnyguru]

(b) live with the miniscule and peculiar supplies Dell builds in, and use an inferior low-power GPU.

That's why you don't buy a Dell (or HP or Lenovo) in the first place. 😀

Lesson learned, I suppose.

 

[xVFallen_KingVx]

Yeah. Optiplex 9020 doesn't have standard power connectors. So not only are you going to have this janky PSU outside the case, but you're going to need an adapter. It's going to look and work like ass.

Best thing to do is buy a new case, PSU and motherboard. If you make sure the motherboard supports the CPU and RAM you're using today, it shouldn't be too expensive.

What type of adapter?

 

[tomreedtoon]

That's why you don't buy a Dell (or HP or Lenovo) in the first place. 😀

Lesson learned, I suppose.

Cute reply, but I have had several Dells, and compared to...say, Mac's...they hold up and are repairable. My concept was to get a SFF Optiplex 9020, which is cheaper than the MDF version BECAUSE of that capability, and because most dimwits can't conceive of having a PSU outside the main system. (Um...laptops have that, y'know?)

If doing it makes the system affordable, then there's a new business to be found. I would mount the SFF and its external ATX supply on a board for easy transport. This is a blind spot for a lot of computer people, but not for me. I don't care how it looks and I don't care about flashing LED lights on the fans. I just want an affordable working system, and leave the fashion design to RuPaul.

 

[tomreedtoon]

What type of adapter?

The adapter is sold a lot of places. Here's a typical example from eBay. I don't like Amazon, but they also have similar ones there too. https://www.ebay.com/itm/New-24-Pin...287787?hash=item42179207eb:g:smsAAOSwN~deqqac

 

[jonnyguru]

Cute reply, but I have had several Dells, and compared to...say, Mac's...they hold up and are repairable. My concept was to get a SFF Optiplex 9020, which is cheaper than the MDF version BECAUSE of that capability, and because most dimwits can't conceive of having a PSU outside the main system. (Um...laptops have that, y'know?)

If doing it makes the system affordable, then there's a new business to be found. I would mount the SFF and its external ATX supply on a board for easy transport. This is a blind spot for a lot of computer people, but not for me. I don't care how it looks and I don't care about flashing LED lights on the fans. I just want an affordable working system, and leave the fashion design to RuPaul.

Dells are fine. That wasn't my point.

But Dell, HP and Lenovo make these PCs like this, with proprietary motherboards, power supplies and chassis, to intentionally block the upgrade path. To entice you to run out and buy a new PC. I think they learned the term "planned obsolescence" from the auto industry. 😀

You're a corner case by willing to use an adapter and run a PSU outside of the case. That's fine. I'm not judging.

There's many people here that have had essentially the same PC for 10+ years simply because they started with standard parts. Not a Mac. Not a Dell. But ATX or SFX (as defined by Intel) form factor cases, with ATX or SFX form factor motherboards and power supplies with standard ATX connectors.

Need a new PSU, swap out with a standard PSU that fits inside the case. Need to upgrade to a next generation CPU that your motherboard doesn't support? Swap out with a standard motherboard that screws right into the same place as the old one. The initial cost is a little higher, no lie (well... higher than Dell. Not higher than a Mac.) but the upgrade path is nearly infinite and long term expense much lower.

Like you said, your functionality is still in tact. Will it look good? Nope. But you don't care. That's all that matters.

I'm not saying I'm right and you're wrong. If that were the case, I wouldn't have continued to advise you in post #5. Just trying to point out why getting proprietary Dell and trying to upgrade it is a bit more... shall I say... awkward?... then just sticking with standard parts in the first place.

 

[tomreedtoon]

Dells are fine. That wasn't my point.

But Dell, HP and Lenovo make these PCs like this, with proprietary motherboards, power supplies and chassis, to intentionally block the upgrade path. To entice you to run out and buy a new PC. I think they learned the term "planned obsolescence" from the auto industry. 😀

You're a corner case by willing to use an adapter and run a PSU outside of the case. That's fine. I'm not judging.

There's many people here that have had essentially the same PC for 10+ years simply because they started with standard parts. Not a Mac. Not a Dell. But ATX or SFX (as defined by Intel) form factor cases, with ATX or SFX form factor motherboards and power supplies with standard ATX connectors.

Need a new PSU, swap out with a standard PSU that fits inside the case. Need to upgrade to a next generation CPU that your motherboard doesn't support? Swap out with a standard motherboard that screws right into the same place as the old one. The initial cost is a little higher, no lie (well... higher than Dell. Not higher than a Mac.) but the upgrade path is nearly infinite and long term expense much lower.

Like you said, your functionality is still in tact. Will it look good? Nope. But you don't care. That's all that matters.

I'm not saying I'm right and you're wrong. If that were the case, I wouldn't have continued to advise you in post #5. Just trying to point out why getting proprietary Dell and trying to upgrade it is a bit more... shall I say... awkward?... then just sticking with standard parts in the first place.

Thanks for the reply. I'm just trying to find a way to game the system. Any way to beat the preplanned obsolescence is good. And I appreciate you being polite with me about this.

As it is, right now I'm having to replace the motherboard in my Optiplex 9020 minitower. I was upgrading from the i3 to an I5-4590 quad core processor. Apparently the socket for this processor (the LGA 1150) has connectors that will bend in a gentle breeze. I've done this before in earlier systems, and I know how to be gentle with CPU's. But the Optiplex wouldn't boot, and I discovered a few of the pins on the socket were bent. I may have tightened down the heatsink/fan too much; maybe they don't need to be fully tightened? (It's actually fortunate in a way: I need a larger heatsink for that processor, which I only learned from my research.)

So, live and learn. I know this is the wrong forum for this, but I'll repost that elsewhere. Again, thank you.

 

[Karadjgne]

Concept design. Using whatever psu you'd like, pull off the top cover. Mark out on the SFF side panel the fan mount holes and cut a hole in the side panel large enough to accommodate the fan draw and the 4 fan mounts holes. Replace the fan screws with longer 6/32 from the inside, a single nut on the outside. Put psu back together. Cut a slot below the fan hole to receive the power connectors and cabling. Mount the psu using the 6/32 screws sticking out from the fan, exhaust pointing up. Second washer/nut on the inside of the panel.

Psu direct grounding, minimal impact to looks, increased case ventilation (Dells were really bad for that), no extra boards and an all in one pc without a janky psu flopping in the breeze.