PSU needed: special size requirement (TFX-ish size required)

ppeterka

Junior Member
Jan 28, 2009
6
0
0
ppeterka.net16.net
Hi all!

I'm in the middle of a modding project (let's just say, this is a ridiculously idiotic and highly impossible project), and yesterday my already modified PSU died...

The available space for the complete PSU with cooling is (be prepared): 20cm x 9cm x 4.2cm

This can be done easily using a picoPSU, if the target config is an Atom based system... But the targeted configuration is a bit more power hungry:
Intel i3-530 on a H55 motherboard, coupled with an AMD 5750, working off of a 2.5" HDD, and absolutely no ODD.

So this kinda looks like impossible to fit. NOT. TFX power supplies almost exactly have the same inner dimensions, and I can even fit 2 pieces of 2cm thick 4cm fans to cool it quite nice.

My original choice was the LC Power LC400TFX. Well, to tell the truth, this was my only choice, as here in Hungary, I couldn't find anything else at the time...

The mods I did on the PSU to fit:
- unsoldered the primary caps, and attached them using short leads, so I could put them horizontally
- Had to cut 1mm from the fins of the heatsink of the switches on the primary side to be able to employ proper electric insulation from the case
- had to put the passive choke on the outside of the PSU case, another pain in the ass having it covered and properly insulated

I would buy it again, but this time I'd like to opt for a little bit better design, if there is any. I mean, this PSU has some lowly efficiency, which hurts a lot in such a small enclosure with barely enough ventillation, so it would be nice to have an 80+ rating. Also, as the whole rig would only consume around 230W of power (Prime95+Furmark, absolute worst case), I think a smaller power PSU would do - given it's potent enough on the 12V rail.

What do you recommend?

Edit:
On the way to work, I just had a new idea to solve the problem in an innovative way. What would happen if I bought two of the external power brick - internal DC-DC converter things like the picoPSU used for low power mini ITX machines. I could have 2pcs of 120W 90+ converters, and use them in parallel (one would have the mobo 24 pin connector and the HDD, the other one would supply the 4 pin on the mobo and the 6pin on the VGA) which in theory would be enough. Or from China, I could get 150W or even 200W pieces, which do seem to be enough - given I can find adequate power bricks for them... Any thoughts?
 
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Zap

Elite Member
Oct 13, 1999
22,377
7
81
What do you recommend?

For a TFX-ish PSU? Seasonic. Seasonic makes a very efficient and very high quality 300W unit. http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=190

On the way to work, I just had a new idea to solve the problem in an innovative way. What would happen if I bought two of the external power brick - internal DC-DC converter things like the picoPSU used for low power mini ITX machines. I could have 2pcs of 120W 90+ converters, and use them in parallel (one would have the mobo 24 pin connector and the HDD, the other one would supply the 4 pin on the mobo and the 6pin on the VGA) which in theory would be enough. Or from China, I could get 150W or even 200W pieces, which do seem to be enough - given I can find adequate power bricks for them... Any thoughts?

Read jonnyguru.com's Pico PSU roundup. http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=207

Otherwise the idea seems solid, but if you're making something small and then you have large power bricks...
 

ppeterka

Junior Member
Jan 28, 2009
6
0
0
ppeterka.net16.net
For a TFX-ish PSU? Seasonic. Seasonic makes a very efficient and very high quality 300W unit. http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=190

The review shows the PSU to be quite a good one... Wish I could find one here in Hungary... I'll try to catch one...

The only problem it might have is that its innards seem to be taller than the ~4cm I have available... Basically I'm trying to get an 1U PSU, but a very small one...

Read jonnyguru.com's Pico PSU roundup. http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=207

Otherwise the idea seems solid, but if you're making something small and then you have large power bricks...

I read it, it was quite a thought-raiser for me, very interesting article, with very interesting conclusions. But after checking prices, it seems that this would be an expensive way for me... An M3 mentioned in the article would set me back ~$100, and 2 is needed, not to mention the quality power bricks needed.


Meanwhile having had a little time to browse, I found the Be quiet! TFX300W unit:

http://extreme.pcgameshardware.de/n...8394-preview-quiet-tfx-und-sfx-netzteile.html

(it's in German, but the pics speak for themselves) This seems to be much better built than my previous PSU, the LC Power one, features active PFC (at least it says so), and seems to have better efficiency, while - with the exception of the primary cap - seems to stay below 4cm of height... Does anyone know about this manufacturer or exact product? The ratings seem to be OK, but are they true? It's not very expensive, I can get a hold of this for around $60...

Edit:
I found a review of this PSU (Original in german, this is translated to English by Google: http://translate.google.de/translat...t-bqt-tfx-300w.htm&sl=de&tl=en&hl=de&ie=UTF-8 ), and to my amazement, it is better than it first seemed! It is fully capable of providing the rated power, and almost 11% more - while having acceptable stabilty on the rails... At first glance I expected it to provide around 250W of power, which would be enough for my system planned, but it wouldn't have adequate safety margin to sustain operability... Considering the 80+ rating, and the very nice price, I think I fell in love with this unit...
 
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