What's better - 90W laptop adaptor OR 80PLUS Bronze PSU?

I'm planning to build a low-power, value HTPC. I'm really undecided if I should go for an 80PLUS Bronze Seasonic PSU OR a laptop adapter from Cooler Master (Energy Star certified).

SETUP 1. I go for the laptop adapter. I'd have to choose a special Intel mini-itx mobo (DH61AG) which is pretty expensive. Mini-itx mobo + laptop adapter = very low power

SETUP 2. I go for Seasonic PSU. I get to choose any cheap micro-atx mobo. Micro-atx mobo + Seasonic PSU = low power but a bit more than the above setup, far less expensive

(SETUP 1 has a mini-itx mobo which consumes less power than micro-atx, not to mention a very efficient efficient power adapter)

I will be pairing the mobo with Sandybridge Pentium G620.

The big question is - is SETUP 1 really going to save me a SIGNIFICANT amount of power (in terms of watts) over SETUP 2?

For a quick reference, see the power measurements here DH61AG

Eben

Posted 2012-10-25T18:18:53.953

Reputation: 1

1This question can't be answered. It depends on a lot of things, starting with how often you actually will use the HTPC. How expensive your power is and how expensive the components are. If one is quieter than the other (important for a HTPC), etc etc. – Hennes – 2012-10-25T18:21:33.440

Welcome to Super User, Eben! Please read the [FAQ], especially the part about shopping recommendations. Your question is too localized to a specific situation such as yours to be generally useful for a broader audience. – slhck – 2012-10-25T18:41:54.343

Answers

There is a misconception! Mini ITX does NOT necessarily consume less power than micro, or full-size ATX! This is just a form factor, nothing else. Theoretically, in some cases, it is still possible to use ~140W CPUs in miniITX motherboards, but in most cases this is not the situation.

My personal opinion would be to go with a cheap microATX, and use the money to get a highly efficient PSU, and a good CPU with low dissipation, like the Core i3-3220T.

There are very small microATX motherboards, like the LGA 1156 ASRock H55M-LE I bought, measuring 24cm x 20.3cm, but ASRock has similar form factor boards in the series with -LE, or -xxS postfix (example for H61 chipset: H61M-HVGS). I can recommend them, my board is very stable despite being in a very undersized house.

Also, be careful to choose the right PSU for the assembly! This computer will consume very low amount of power. Usually PSU's have the best efficiency at around half of their rated power output! So in this case I'd chose the smallest available 80+ PSU at hand. Do not get over 350W, even that is way too much for this kind of setup...

Also recommended reading when PSUs are considered: Jonny Guru

(FYI, my computer is built in the housing of a dead 16 port 1U router, measuring 20.3x44.4x4.4cm, and has an i3 540 CPU and an ATi 6570 inside.)

ppeterka

Posted 2012-10-25T18:18:53.953

Reputation: 674

Nope, absolutely not. The biggest thing is going to be power draw, not power availability. If you were going to use the same cpu, gpu, memory, hdd ect for the system, and literally the only diff is the power supply(and subsequently, the mobo), id say go for the one that will provide you the best value. In this case, the Seasonic (great brand) will do wonders.

user76211

Posted 2012-10-25T18:18:53.953

Reputation: