Failed Mini-ITX build (insufficient power)

[Sparhawk909]

When my shiny new Sapphire Low Profile Radeon 7750 came in, I promptly put it in my mini-ITX case, hoping to get some Diablo III gaming in to replace the Radeon 4290 IGP.

Woops! As soon as D3 loaded, 0.5 seconds later the computer shut down. Unfortunately my power supply can't handle the load.

Antec ISK 300-65 with 134.9 W HP power brick
AMD Phenom II 910E CPU + stock heatsink/fan
MiniX 890GX-USB3 motherboard
2x Patriot PC3-10600 sodimm
Corsair Force GT 60 GB SSD
Asus DVDRW slim
2x 80mm fans

Looks like the 135W power supply can't handle the load. I unplugged the fans and DVDRW, but the computer still shut down. I have a few alternatives, but would like some advice. I really don't want to send more money to get an Intel CPU and motherboard after I spent $140 on the 7750.

Get a new mini power supply? Get a pico power supply? What did Antec owners do?
I could replace the SSD with a 5400 RPM 500 GB HD. How about undervolting the CPU?
Wait for a low profile Kepler from nVidia that's using even less W?

Maybe I'm a few Watts short? Maybe a lot?

 

[Zap]

FWIW using a Core i5-2500K and Radeon 6670, I pull around 138W from the wall during gaming. All stock clocked, so doesn't use much power. The Phenom II will be drawing a bit more power. I'm using the stock 150W PSU in an Antec ISK 300-150.

I wonder if your power brick is rated for peak wattage instead of continuous?

Potentially you can ghetto rig something to take care of immediate power needs. For instance maybe get a separate 12v brick and wire it into the CPU 4-pin connector (buy an extension to modify). That way you combine the two bricks.

 

[fr500]

The power brick might be 300w... it doesn't matter, the DC-DC converter is rated for 65w. You need a higher rated DC-DC converter

 

[notarat]

Get a Pico-160 Power Supply & 160W Power Brick.

 

[Sparhawk909]

FWIW using a Core i5-2500K and Radeon 6670, I pull around 138W from the wall during gaming. All stock clocked, so doesn't use much power. The Phenom II will be drawing a bit more power. I'm using the stock 150W PSU in an Antec ISK 300-150.

I wonder if your power brick is rated for peak wattage instead of continuous?

Potentially you can ghetto rig something to take care of immediate power needs. For instance maybe get a separate 12v brick and wire it into the CPU 4-pin connector (buy an extension to modify). That way you combine the two bricks.

I have an old ATX power supply. Is the motherboard power supplied through just the 4-pin or through the 20-pin as well? So connecting just the 4-pin would draw the CPU wattage from the total load?

 

[JoeUser]

I have an old ATX power supply. Is the motherboard power supplied through just the 4-pin or through the 20-pin as well? So connecting just the 4-pin would draw the CPU wattage from the total load?

As far as I'm concerned if a motherboard has a 20/24-pin plug and a 4-pin plug they NEED to be used! At the VERY least the 20 pin needs to come into play.

 

[onin]

What case are you using? maybe you can use one of those drive bay PSU. (but it might be overkill)

 

[leeleatherwood]

I have heard of people using an XBox 360 power supply, pretty ghetto tho, I would rather just get a new psu or case if needed.

Or, there is this: http://www.mini-box.com/M4-ATX?sc=8&category=981 250w max, 12v input.

 

[runs2far]

The power brick might be 300w... it doesn't matter, the DC-DC converter is rated for 65w. You need a higher rated DC-DC converter

This a million times this.

You are running of a 65 Watt DC-DC converter, get a PicoPSU they easily fit in almost any build.

Is that HP supply 12 Volt or 19 Volt?


EDIT:

Looked up the case it takes 19V and I assume the HP brick is 19V as well.

Solution 1:
brick + pico (144W @ 80$): http://www.amazon.com/Mini-Supply-P...qid=1347346356&sr=1-1&keywords=PcioPSU+150-XT

Solution 2:
Just pico (120W @ 43$): http://www.amazon.com/PicoPSU-120-W...qid=1347348007&sr=1-1&keywords=PicoPSU-120-WI

 

[JBark]

The jonnyguru review of the 120-WI-25 showed that it worked very well with a 19V supply, so I'd think that would be an easy way to go.

 

[Sparhawk909]

Thanks for all the replies. Are you sure based on the components I have listed along with the Radeon 7750, that that 120W pico PSU will be able to run my setup?

 

[fr500]

Not 100% try a pico psu 160xt to be on the safe side.

 

[Dangman]

I agree with fr500 and go for the larger PicoPSU considering that you have an AMD CPU.

 

[Sparhawk909]

I see the Pico PSU 160XT on the mini-box website for $50. However, it does not come with a power brick.

My HP power brick is PA-1131-08HC, 19V and 7.1A (135W), so it would not work with this Pico PSU, correct? I would have to get the power brick from the website as well.

With taxes and shipping (located in Canada) totalling well over $100, wouldn't it be better getting a Flex PSU or one of those Seasonic mini-ITX power supplies and doing some dremelling?

Thanks for any more suggestions and answers.

 

[runs2far]

The Pico PSU 160XT requires a 12V input and your 19V power brick will not work with it, it may actually fry your computer if the Pico PSU does not feature over voltage protection.

The PicoPSU-120-WI-25 supports input from 12-25V making it usable with your brick, however this unit will probably be a little to weak, as the system with GPU should be in the 80-100 watt area when stressed and this model can only handle 80 watt of constant load

If you want to use a standardish PSU in stead, then try it, but there is a risk that it will not fit in that case.

 

[Sparhawk909]

Thanks all. It would seem the most elegant solution would be the Pico 160 XT kit.

http://www.mini-box.com/picoPSU-160-XT-192W-Adapter-Power-Kit

However, after shipping it would be $102. I already sunk $140 into the video card, so $242 to play Diablo III at 1680x1050 high settings on a mini-ITX? No thanks.

I will sell the Radeon 7750 to recover my costs. Anyways, here are a few pics of my build of what could of been.

 

[fr500]

Why not sell the case and get the 250w version? it's only $80