Overview Features Instructions Performance Forum Downloads Products OrderV4 Reseller Contact

Welcome to the Apollo Forum

This forum is for people interested in the APOLLO CPU.
Please read the forum usage manual.

All TopicsNewsPerformanceGamesDemosApolloVampireAROSWorkbenchATARIReleases
Documentation about the Vampire hardware

Vampire PSU + Meanwell

Ozzy Boshi

Posts 27
04 Jan 2021 20:39

Hello all
    My a1200 + v1200 is powered by a MEAN WELL RT-65B
    This is the product i bought 2 years ago
    Now i read here that I must put a resistor in the 12v rails
    At the moment I didnt solder the resistor in the meanwell, that means that the 12v output of the meanwell goes straight into the amiga square power connector.
    I'd like an official suggestion from the apollo team guys, is it risky to continue using a meanwell this way? so far no problems at all but maybe over time i will damage the meanwell or (worst) the amiga itself.
    My v600 instead is powered by its old commodore power supply from the 90's and no problems so far, is it risky?
    I asked a professional opinion to EXTERNAL LINK that provides psu for amigas.
    The answer was, and quote:
    "Vampire.... to be honest, as the Vampire is known for high current draw at 5VDC it would be better to use DUO this platform as it's giving more current on 5VDC rail."
    I see from older posts that apollo team doesnt recommend a particolar psu, any regular psu should be good, so I am very confused now and I'd really like some advice since psu are a very sensitive subject.

Eric Gus

Posts 441
05 Jan 2021 03:20

I use one for my A500 and I can't say it required the 12v dummy load resistor .. but then again I have an active working floppy drive on it so maybe thats why its unnecessary..

in that github its also listed as "Dummy load (optional)" ..

Gunnar von Boehn
(Apollo Team Member)
Posts 5099
05 Jan 2021 07:49

Ozzy boshi wrote:

"Vampire.... to be honest, as the Vampire is known for high current draw at 5VDC it would be better "

Actually the Vampire is not known for high current draw on 5V.
Most Amiga CPU accelerators draw more power than Vampire.
In comparison the Vampire is basically "green" computing.

The meanwhell PSU that you have already has 5A,
your seller recommends you to replace it with a 4A PSU.

You Vampire needs 0.5A

Ozzy Boshi

Posts 27
05 Jan 2021 07:49

in my case i have a lot of things attached:

- an arduino ethernet module (vampire)
- 2 leds (vampire)
- real floppy drive
- squirrelscsi (pcmcia port)
- ide2cf interface

but all of them i assume uses the 5v

Andy Hearn

Posts 334
05 Jan 2021 22:09

well, i wouldn't say any of those things you've listed really pull any amps/watts. in fact the ide2cf adapter is probably totally passive unless it's got an LED on it. maybe the floppy drive is going to be the biggest power draw - only when it's spinning? not like your running an old 52meg quantum fireball scsi drive in there :)
and you've swapped out your hard drive for a compact flash card, so thats pretty much the best power saving right there.
the LED's can usually be measured in milliamps. i think the arduino module is 3.3volts...?

my V1200 setup is pretty much the same but i've got additionally a gotek on the floppy port, and instead of your squirrel scsi card, i have a PCMCIA network card.
All running off of a standard amiga PSU for days.

when i used to run a Blizzard1240 i'd have that hung off of an A500 PSU, not for any real reason more than i'd read that it could take the current loading better. and i had a PicoATX-PSU setup with an 80W AC-DC brick running my blizzardPPC+bvision A1200.

if anything, i'm toying with the idea of figuring out a way of powering my V1200 machine via a USB battery pack, or PoE network power splitter...

the only machine that's killed a PSU is my A4k. and thats because i screwed up thinking i could run a 300W flex-ATX PSU in it. turns out that even at 300Watts, couldn't handle the 5V loading of a fairly well expanded A4k. so that's now got a 650W SFX psu - as that's about the level i needed to get to, where a PC PSU could match or beat the original A4k PSU's 180W on the 5V line.

oh wait, no i forgot. my A4kT (why oh why did i sell you *sob*) has a PC-AT style power connector. that machine fully loaded would melt holes into the PSU connector plugs "tongues", and the PSU would need replacing every year or two. 

so anyway. PC power supplies these days are all about the 12Volt lines. Amigas are all about the 5Volts. So whatever you plug in, look for at least 3amps at 5volts, make sure you get a PSU that can run a minus 12Volt line as well, otherwise your audio is going to get a bit screwy.

not that i'm shilling for icomp, but at least they're having a go at doing a good replacement PSU it seems... EXTERNAL LINK

posts 5