Prototype SFFtime presents: U-ITX - 7L lightweight console case that fits 3slot GPUs

Killinger

Average Stuffer
Jun 25, 2018
76
56
Putting a rtx5090 fe inside a U-ITX remains a poor idea for gaming for 2 reasons, at least :
  • Poor thermal that will force important power reduction (-30% as it the max)
  • With the arrival of DLSS4, rendering résolution would be moré and more 1080p that could lead to cpu bottleneck, especially as you have to reduce the cpu tdp inside the U
For gaming, aim for the rtx 5080 max inside the U-ITX.
Couldnt possibly disagree more, in fact im already running this same system albeit with a inno3d 4070 ti super in a Midori 5L. A 9800x3D can run without any pbo offset under a AXP90-x47 FC, Im currently running mine on a L9A and only with a -20 offset

the entire point of going console with a 5090 would be to isolate the gpu and cpu intakes. By simply flipping the gpu the riser doesnt block the exhaust, you’d easily be able to run the card at its full 575w.
 

vinnyoflegend

SFF Lingo Aficionado
Mar 18, 2022
114
64
Very low this time, but from the next batch I will have regular stock quantities.
Was there stock in the black version ? Seems like only white is available 😅
Looks like a b-stock of the black U-ITX came back into stock, not sure if that's right but you should snag it if you want it :D

 
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MarcParis

Spatial Philosopher
Apr 1, 2016
3,732
2,873
I feel like I mostly disagree with this and that U-ITX should be a nearly optimal 5090 gaming solution because 7800X3D and 9800X3D run cooler than 5800X3D, and I can attest to the AXP90 being basically enough for the 5800X3D, it's definitely enough to keep it cool with CO applied. Without CO there is a slight amount of throttling in play.

Now i must admit for workstation use, a 5090 ought to be paired with a 16 core class CPU and deserves a stronger CPU thermal solution. Since this is also me I do have second thoughts about whether a U-ITX is for me, I think it still may be because i always have too many computers and don't actually need to put a 16 core in the SFF rig.
Well, please read my full review & experience inside the U-ITX, using an R7 9800X3D and RTX 4080 FE..:) (check my signature)
My comment about putting a RTX 5090 FE is based on experiment, not theorical.

Stating that a stock R7 9800X3D can be tamed by a 47mm tall cooler is totally wrong. You need to massively undervolted & limit its power. For some applications (like some games) it is ok, for others, you will limit performance.

Similarly I was obliged to block my RTX 4080 FE fans to 1100rpm, otherwise, turbulence & fan noise were simply too much distractive...without saying my back SSD was simply cooked by the GPU exhaust air (reaching 70°C doing nothing).

At the end you can even compare U-ITX vs N-ATX cooling/thermal performance :
U-ITX : https://smallformfactor.net/forum/t...9800x3d-and-the-rtx-4080-fe.19941/post-291355
N-ATX : https://smallformfactor.net/forum/t...n-atx-v2-complete-build-log.17997/post-291941

Don't get me wrong, the U-ITX is a great case and I love it! However it has its cooling limitation. Of course you can put a R7 9800X3D paired a RTX 5090 FE inside but you will have to undervolt/downclock them massively to avoid thermal throttling & huge noise.
As stated, my advice is to limit CPU to 65W and GPU to 250W inside the U-ITX.
 
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Killinger

Average Stuffer
Jun 25, 2018
76
56
Stating that a stock R7 9800X3D can be tamed by a 47mm tall cooler is totally wrong. You need to massively undervolted & limit its power. For some applications (like some games) it is ok, for others, you will limit performance.
Im telling you that I own that hardware and am already doing it and getting full performance. Zero difference vs a peerless assassin 120 and an AXP90-47 FC. You can offset PBO but you dont need to. I only play esports titles and hit the cpu hard, trust me its not being bottlenecked.

On top of all that, the new 9000 series allow for negative offsets down past -30 if you absolutely must be sub-80c.
 

riba2233

Shrink Ray Wielder
Original poster
SFF Time
Jan 2, 2019
1,814
2,416
www.sfftime.com
Imho it all comes down to how much noise you are ok with, there is always an option of brute forcing it with some extra RPMs but if you want a really quiet build then you will have to limit power on some high tier components yeah. And if you are ok with some components running near their higher temp range which shouldn't be an issue for modern components.
 
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OziTwo

Minimal Tinkerer
New User
Feb 2, 2025
3
1
Looks like a b-stock of the black U-ITX came back into stock, not sure if that's right but you should snag it if you want it :D

Good lookin out Vinny but I settled on the White case 😅.
 
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MarcParis

Spatial Philosopher
Apr 1, 2016
3,732
2,873
Im telling you that I own that hardware and am already doing it and getting full performance. Zero difference vs a peerless assassin 120 and an AXP90-47 FC. You can offset PBO but you dont need to. I only play esports titles and hit the cpu hard, trust me its not being bottlenecked.

On top of all that, the new 9000 series allow for negative offsets down past -30 if you absolutely must be sub-80c.
Once again, esport games are not hitting hard the CPU power consumption. eSports games loved 3D VCache to generate very high frame rate.

Basically in eSports games, your cpu is using around 50-60W, even at 500+ frames.

However some other games like Dragon Age The Veilguard or Starfield are exceeding easily 100W CPU power usage.
 

Killinger

Average Stuffer
Jun 25, 2018
76
56
Once again, esport games are not hitting hard the CPU power consumption. eSports games loved 3D VCache to generate very high frame rate.

Basically in eSports games, your cpu is using around 50-60W, even at 500+ frames.

However some other games like Dragon Age The Veilguard or Starfield are exceeding easily 100W CPU power usage.
Im literally measuring my output wattage and am happy to share it with pictures of my voltage meter. Im happy to post photos of this to show how wrong you are, but you seem to be incredibly misinformed as you dont actually have the hardware in-hand. I’d be happy to benchmark whatever you’d like at whatever resolution you need to show you how incredibly incorrectly uninformed you are about this particular subject.

This is a thread to celebrate SFFtimes Cases, lets not derail this thread any further with flat earth level disinformation and lets focus on the actual cases here.
 
Last edited:

Atlas

Chassis Packer
Nov 14, 2022
16
9
Well, please read my full review & experience inside the U-ITX, using an R7 9800X3D and RTX 4080 FE..:) (check my signature)
My comment about putting a RTX 5090 FE is based on experiment, not theorical.

Stating that a stock R7 9800X3D can be tamed by a 47mm tall cooler is totally wrong. You need to massively undervolted & limit its power. For some applications (like some games) it is ok, for others, you will limit performance.

Similarly I was obliged to block my RTX 4080 FE fans to 1100rpm, otherwise, turbulence & fan noise were simply too much distractive...without saying my back SSD was simply cooked by the GPU exhaust air (reaching 70°C doing nothing).

At the end you can even compare U-ITX vs N-ATX cooling/thermal performance :
U-ITX : https://smallformfactor.net/forum/t...9800x3d-and-the-rtx-4080-fe.19941/post-291355
N-ATX : https://smallformfactor.net/forum/t...n-atx-v2-complete-build-log.17997/post-291941

Don't get me wrong, the U-ITX is a great case and I love it! However it has its cooling limitation. Of course you can put a R7 9800X3D paired a RTX 5090 FE inside but you will have to undervolt/downclock them massively to avoid thermal throttling & huge noise.
As stated, my advice is to limit CPU to 65W and GPU to 250W inside the U-ITX.
I had an i9-13900K @P1/P2 95W with an undervolt + RTX4090 FE @85% PL in the U-ITX. Good temps and reasonable noise level. 🙂
And no performance hit @4K.
 
Last edited:

MarcParis

Spatial Philosopher
Apr 1, 2016
3,732
2,873
I run my 9800 at 105 eco mode. There's a white model now. Wish there was that option before. 🤐
Best & easy way to limit power of your cpu is :
  • Activate PBO
  • Setup manual PPT to the max power value you want : depending of your motherboard is either 75W (like for Asus/MSI) or 75000 mW (like for Asrock)
 

MarcParis

Spatial Philosopher
Apr 1, 2016
3,732
2,873
I had an i9-13900K @P1/P2 95W with an undervolt + RTX4090 FE @85% PL in the U-ITX. Good temps and reasonable noise level. 🙂
And no performance hit @4K.
No performance hit with a rtx 4090fe with power limited at 85%? Seems unlikely, most probably it is not noticeable like -5%

On cpu side, it should not be a bottleneck at 4k.

Are you using DLSS?
What is your gpu power consumption, fan speed and core usage while gaming?