M1-ATX 90W PSU Usefull Observations

**James141** · 03-10-2005, 05:08 AM

I have seen a lot of posts from people asking if a 90W PSU is enough, hopefully this post will give you some guidance.

I recieved my M1-ATX 90W PSU yesterday I installed it in my system and ran some power test as discribed in Easiest Way To Check System Power Usage?

I was worried I would not have enough power.

I got the following results (please see my signature for my system specs)

Bench PSU running at 13.88V

Hard Off 0.12W
Soft Off 1.37W
On MB/Ram/Processor/Small Fan 30.W
On MB/Ram/Processor Peak/Small Fan 33.86W
USB Keyboard (Backlit) 1.48W
USB Hub 0.12W
USB Hub/KB and Mouse 0.87W
HDD ~10.1W
Everything ~39W

So from my experiance as long as you stick to a smallish mobo + sensible processor + sensible GFX card you will be more than fine with a 90W PSU. As with all my things connected I still have ~50W to play with but obviously I dont want to max it out.

It is worth noting that the LED port on the M1-ATX is actually really usefull. From what I have read it is often overlooked, it is solid on when the pc is on but while the pc is shutting down it blinks long pulses and when the pc is off but the board is in soft off mode it blinks slowly and it goes off totaly when the board is in hard off mode. It is a very usefull indicator of what the board is doing.

I also found that my PSU shipped yesterday works fine with the soft off/hard off timings

and does not suffer from bugs noted in other posts.

All in all so far it seems a very good bit of kit and at £45 you cant really grumble.

More To Come.......

**KyferEz** · 03-10-2005, 11:04 AM

Question: Did you do any testing of the complete setup running and playing some cpu/ram/hd intensive apps, like playing DivX? Or something less intensive like just playing mp3? Or were these individual tests simply powering the components? There is a big difference...

If you didn't test it with a processing load, you will find current consumption spikes quite a bit when you do. You will notice sustained current rates are higher, as well as peak currents even higher. It's something you should look into if you havn't already.

KyferEz

**James141** · 03-10-2005, 12:24 PM

Sorry, I should have made it clearer this was just booting to the bios stage. as the bench PSU I was using could not provide me enough AMPS to boot the whole system with the hdd.

I did test it in my car and got similar results with the full system but as I dont have a screen yet it was impossible to do any proper tests as I didnt fancy lugging my monitor down the drive

I will post more/better results when I get my screen and can get it fully working in my car

**MSUC5Vette** · 03-10-2005, 04:55 PM

Thanks for the info James, I am looking at the same supply.

Anyone else who is using this supply I would love to see your system setup and what you think of the supply.

**Nico3k** · 03-10-2005, 05:22 PM

This is very interesting information. Thanks for sharing
The PC can use up to 7 watts more when put under full stress, so you may want to consider this aswell.

Right now I am thinking how I will manage my power; I have a M1-ATX, but I need to power
-1.2GHz ITX Board with PCMCIA Slot
-512MB PC2100 DDR
-802.11 PCMCIA Card (5v)
-802.11 1Watt Wireless Amplifier (1.2A on 12v+ line)
-7" LCD Screen
-USB GPS
-USB Touchscreen
-USB OBD-II Controller
-60GB Laptop HDD
-Slimline Slot-load CD-RW/DVD Drive

I have a feeling that the M1 won't be able to power all this; I wonder if there's a way to add a 2nd power supply. Anyways sorry for thread-jacking, great observations.

**rando** · 03-10-2005, 06:21 PM

You need to consider each power rail independently. For instance, your system might need only 39W total power but if it needs more than 24W on the 12V rail then the M1-ATX isn't appropriate.

Here is a more meaningful power classification for some popular carpc ATX supplies.
3.3V/5V/-5V/12V/-12V/5VSB

M1-ATX: 33/50/na/24/.18/7.5 *50W max combined 5v,12V rails.
Opus 90W: 19.8/30/na/30/.24/7.5
Opus 150W: 33/50/na/60/.24/5

@Niko: If you look at your list of equipment, you'll notice you have very little on your 12V rail; .8-1A for your LCD and maybe 100mA for your fans. Your system board runs primarily off the 3.3V rail. Everything else is at 5V -- and probably not close the 10A limit of the M1 or Opus 150. In fact, any of the 3 supplies would probably work fine for you.

** Oops sorry, I missed your 1.2A wireless amplifier. That combined with your LCD pushes you right up to the limit of the M1-ATX 12V rail. The Opus 90W might be a better choice -- but then you give up growth room on the 5V rail.

**James141** · 03-11-2005, 04:53 AM

Hopefully borrowing a dremmel tonight so I can get it all fitted in to the NTL box so that should make testing a lot easier. That should allow me to produce some better tests. I will let you all know

That is interesting about the Wattages on the different lines...

**CdRsKuLL** · 03-11-2005, 05:04 AM

lol.. not a cable NTL box ? Also where did you buy your M1 from ?

CdR

**James141** · 03-11-2005, 05:16 AM

LOL yeah an NTL cable box, their TV/Service is cr@p so I thought it was the best thing for all concerned if I got SKY+ and put the NTL box to good use

plus it fits my motherboard, PSU and HDD in perfectly.

I am going to put my project on a web site soon (probably over the weekend) so I will post the link in good time

I got my M1-ATX from Linitx.com I think with VAT + delivery it was about £55

**Scouse Monkey** · 03-11-2005, 08:56 AM

Originally Posted by James141

LOL yeah an NTL cable box, their TV/Service is cr@p so I thought it was the best thing for all concerned if I got SKY+ and put the NTL box to good use

plus it fits my motherboard, PSU and HDD in perfectly.

spot on! Damn i threw one of those out last year. Wel actually someone else threw it in our bin and then my hosuemate found it and I threw it back in as we didnt have cable.