Group buy for the cheap MagicPower 120W MPD-810H DC-DC PSU

Telek · 04-06-2003, 03:50 AM

Hey, would anyone be interested in doing a group buy for the MagicPower MPD-810H (same unit as arise)? I figured we should start a new thread for this. Group buy would definitely be preferable if only to save on shipping since they are located in Taiwan.

What I have so far is this:

Link and Spec Sheet (PDF)

Prices: $74USD each or $63USD (now including cables!) if we have more than 10 units! (confirmed, but add ~$25 for shipping and ??~$5 for import tax??)

This is a 120W+ DC-DC ATX power supply that can be in your hands for a total of around $105USD

Specs:

Code:

input : 10VDC-30VDC

Output    Min.    Rated   Max.     Voltage accuracy
voltage   load    load    load  
+5V       1.0A    8.00A  10.00A    4.95V to   5.15V
+12V      0.0A    1.50A   4.00A   11.25V to  12.75V
-12V      0.0A    0.50A   1.00A  -11.75V to –13.10V
+3.3V     0.0A    5.00A   8.00A    3.00V to   3.50V
+5Vsb     0.1A    0.75A   0.75A    4.80V to   5.20V
                 84.25W 140.15W

* Notice there is no -5V rail (see below)
* Maximum 120W requires 18CFM forced air cooling, otherwise 85W with only convection cooling.
* The maximum total combined output power on the 3.3V and 5V rails is 70W (forced air cooled).
* The power supply includes cables (they are $2, factored into the above price). You can get ATX or ATX w/P4.
* There is already a 2-pin fan header in the PSU (+12V/GND Molex 5045-03).
* The 3-pin header viewable in the picture is PWR_ON/GND/5VSB
* Overvoltage, Overload protection standard with auto-restart
* Protection against wrong polarity
* Input inrush current protection
* MTBF >200000 Hrs per MIL Handbook 217F
* Higher than 70% efficiency when running at rated loads.
* 3-pin input connector (+12V/GND/ACC)

Size: 152.4mm wide * 83.8mm long * 38.0mm high (6" x 3.3" x 1.5")

Prices from MagicPower in Taiwan (confirmed): 1-10 for US$72, 11-49 for US$61 (plus add $2 for the cables)

Shipping will depend greatly on the number of units recieved. For example, shipping of 40 units would cost $175USD (or $4.4 each + cost from organizer to everyone). I'd estimate (rough guess) shipping for 11 units to be around $80USD, 5 units probably $60USD. Tack on roughly $15USD for shipping from organizer to you and $5 for import tax, so you're looking at ~$105 landed on your doorstep. If we get 11 units then it'll be ~$90.

To help you determine your power requirements, check out the NEW system power calculator available from my site website. Keep in mind that those are absolute maximum power draws, not what you'll see under typical use.

The lack of a -5V rail is not that big a deal since you can add one by using only a single component. MC79L05ACP or similar attached to the -12V rail and ground will provide a -5V output rated at up to 1A, however the -12V output will be the limiting factor for current (total output for -5V and -12V cannot exceed 500mA w/ convection or 1A w/ forced air cooling).

Provided that this PSU does not draw more than 600mA on the switched input lead it would be pretty simple to create a basic delayed power-off circuit (or really for any PSU with a switched line drawing less than 600mA).

[Arise info updated Apr 18]

Additionally Arise (located in Massachusetts and California) appears to sell it this same PSU with cables for $98 or $96 if we order more than 10 (confirmed), yes, a whopping $2 discount... I've given up trying to get a bigger discount, they are just silly. MagicPower came down $11 from $72 (15% off!) and Arise gives a measely $2 from $98 (2%)? Well, their loss. They won't even ship to individual addresses! A whole $2 each off 10 units and they will only ship to one address.

So right now ordering from Arise is $33 more expensive for the unit itself, however shipping will probably be about $10 less, and you won't have to pay import tax ordering from Arise (~$5/unit ??) so you're looking around $18 more expensive to order from Arise than to order from MagicPower.

I will report and continue to update this once I hear more.

So who is interested?

Scafremon · 04-06-2003, 04:01 AM

I'm interested.

Not 100% committed yet, but definetly interested.

Telek · 04-07-2003, 07:26 PM

I added price information to the top post.

silentium · 04-07-2003, 09:05 PM

very interested but cant sign on the dotted line just yet

Cadillac_LoungN · 04-07-2003, 09:26 PM

Am also very interested. Just trying to figure out if 120w will be enough for what I need to power. Athalon 1.3Ghz (underclocked to maybe 1Ghz or below to save power) IBM deskstar 20Gb, ATi all in wonder, USB GPS, IrMan, Integrated audio MoBo, and sony 16x DVD-Rom. Anybody have any advice on whether this would be enough. My feeling is that I would really be pushing the limits of 120w. I like this power supply though, looks to be pretty good. Could be a little more efficient, but if it will handle all my components, count me in!

Telek · 04-07-2003, 09:44 PM

If you underclock to 1.0GHz you should be fine. The Athlon 1.0Ghz/1.3Ghz takes ~54/61W max. This thing can put out a little more than 10A on the 5V rail, however I have found that my processor never reaches close to the "maximum" power draw.

If you underclock to below 1.0GHz you could definitely do it.

I added a link for the CPU power graph to the first message.

AMD chips tend to be less power efficient than Intel chips, unfortunately.

Mastero · 04-08-2003, 02:30 AM

input 10~30

car battery drop to 8-9 during cranking and cold start..

check it out ..!

Mastero

Telek · 04-08-2003, 02:42 AM

Possibly, however we had this argument a long time ago, not all cars do. If you have a good battery then the drop will be momentary. If this actually is a problem, add in a tank circuit or a second battery and you're set to go.

The majority of the time people get into their cars and start them, so it's not that big a deal if the computer won't last during a crank, so this isn't always an issue.

During cranking the voltage can easily drop below the 8V minimum required for the sproggy as well, so it's not like that is immune either, albiet it is better off.

Additionally most commercial supplies also have a cutoff around 9-10V. This might actually function below 10V, we'll have to wait to find out.

However this is still a great deal, ~$105 for a commercially produced 120W+ power supply... best deal that has come along yet. We seem to have a few people interested, if we can get the number up to 10 then it'll be only $90 each landed on your doorstep. Very good for what you're getting.

Cadillac_LoungN · 04-08-2003, 03:03 AM

This is just me thinking out loud, but doesn't 70% efficiency seem kind of low. I mean for DC-DC, were only talking about like 10% higher than an inverter/PSU combo right. Maybe if it were up in the 90 percentile, like opus then it would be justified, but for $100 wouldnt it be easier, and cheaper to use an inverter? And there's no startup/shutdown controller on it, and 120w still sounds like it may leave little room for versatility/expansion within the system. I'm still really stuck on this, because yes, it seems like a good deal, but it really doesn't look all that better than an inverter setup and is still a lot more expensive.

mipec · 04-08-2003, 05:27 AM

I'm interested.

Telek · 04-08-2003, 07:32 AM

You do raise a good point, I was very curious about that as well. I wonder if that is real? Does anyone know what the efficiency of the Sproggy is? I wonder if that number is accurate, and if it is, then why is the efficiency so low?

There are a few people in Europe who are intending on getting these PSUs first, I was hoping that we could wait for them to try it out before doing our order. Perhaps then we will have more information.

The guys at Arise in the US seem to be taking their sweet time replying to my emails. Maybe once they do I can ask them for some more information as well as I don't think that the people in Taiwan will understand my request, but I guess that I can try them as well.

Edit:

I just checked, the national LM2587's efficiency rating is 70/80/90% for supplying 3.3/5.0/12.0V with 12/12/10V input. The Maxim data sheets seem to high their efficiency, so I would assume that it would be similar. People claim however that these numbers are pessimistic, but I suppose the only way to tell would be for someone to use an ammeter to tell us. In any case, I asked MagicPower for more info on the efficiency as well, and I am still waiting to hear back from Arise. I'll keep you posted.

kendrick · 04-08-2003, 05:13 PM

m

Telek · 04-08-2003, 07:36 PM

Quote:

Originally posted by kendrick
m

Really? how interesting!

I have updated the price for Arise in the top post. $98 for a single unit confirmed, don't know yet about bulk or custom cable order.

kendrick · 04-08-2003, 07:48 PM

sounds nice but if its gonna restart when i crank i may as well stick to the inverter or get the opus

theedge · 04-08-2003, 07:59 PM

If youre worried about when the cars cranking, a decent cap should take care of that fine.