Lack of power issue?

[Brian]

I have an issue with a A40000 Mediator4000D that I'm thinking might be due to power. When adding Voodoo3000, 100Mb NIC, Spider2 and TVTuner (all PCI) to the system it boots up showing the ROM display after the 30sec delay (system is almost stripped so is just motherboard, memory, 3630CPU card, ScanMagic and the Mediator... no drives, floppys etc). Adding kickflash and VarIO to this setup still produce the ROM display but if I go further and add more cards or replace the small kickflash and/or VarIO with a more powerhungry card the machine does 2 things:

1. It does come up with full power but turn off power and you need to wait 10sec before powering it up again or it will blink the powerled 2 times and then stay on dimmed light.

2. That I could have lived with if it wasn't for the fact that it doesn't produce the ROM display either so it doesn't complete post for what I can tell.

To me this sounds like a power issue or rather a lack of power issue but I want to verify it here and perhaps get a few hints on what to do instead. The PSU is a 400W so I think it should be powerfull enough for this application but if you people think it's not enough I'd get a real heavyduty one (the chassi supports 2 PSU's so the one I have now coule be a slave PSU powering only drives and such).

Another, perhaps even more, likely candidate would be that the PSU is powerfull enough but not enough power reaches it's destination (could also be that not enough of a surtan current is reaching the cards... thinking +12V might be on the low side). This makes me wonder if there's any way of adding more power to the mediator bussboard somehow... preferrably in a safe and nice way?

A less likely candidate (in my oppinion) could be adressing issue cause the above behaviour is exactly the same even when filling all the slots in the Mediator system.

So what to do? Get a more powerfull PSU? remodel the mediator backside to perhaps add 12V and 5V directly to all the slots? Perhaps do both? Or should I digg further into the possibility of an adressing issue?

:help: HEEEEELP PLEASE :help:

[Framiga]

are you speaking about the Mediator 4000Di (for the original case) or the one for PowerTower?

[Brian]

Mediator4000D as in Mediator for A4000D in Towers.

[Brian]

Anyone have any idea? :bump:

[Framiga]

like mine then... no problems with the backplane power lines.

If you have an ATX with a ATX>AT converter, usually the wires are too thin. (above all on the +5V line)

I've fixed it, connecting 3 wires together coming directly from the PSU to the 6 pole Molex/AMP mobo connector. (and 3 GND as well)

My system is way loaded than yours with a (good) 250W PSU.

(2 GFX cards-RepulseGold-XSurf2-PAR+Capture card TBCPlus- 3 HDs-etc)

[Brian]

I use the powerconverter that comes with the Mirage4000Pro so the powerlines to the motherboard is thick and the extra powerlines to the mediator board are the propper ones. I'm thinking it might be a bad/lowquality PSU that's at play here perhaps... a new PSU is on the menu... I'll aim for 700-1KW this time (the range where low quality PSU doesn't venture very often).

[Framiga]

you will wast money. It must be a good quality one. No need of that abnormous monsters

anyway... check with a multimeter the voltage on the mobo connector and then on the backplane (on the 5V rail). If theres a huge difference (anyway it must be not less than 4.9 Volts), you have a problem

[Brian]

Can buying anything for the Amiga ever for real be concidered well spent money? With the lot of hardware that is left to go into this machine it does need a heavy duty PSU... just not sure how much so better be on the safe side and as said before... high quality is hard pinpoint on low/midrange PSU's so a realy heavy duty PSU will help me sort that problem aswell.

The PSU I have now didn't come that cheap and had good reviews back then.. now is not so much and, although this can also be due to the machine been stored for quite some time, the PCU did smell a bit "funky".

[Framiga]

Brian what to say? good luck! :-)

[Brian]

I'll need a hole lot more than just luck but thanx... anyone with any input on the above described behaviour and if I'm on the right track or if not what else I should consider?

[CLS2086]

Hi,
you can use a standard AT PSU, just to power up yours HDD, CD, floppy. That will sighly help your ATX Psu.

[keropi]

when I used mATX psu's with elbox converters I found that they don't deliver a good +5v line so I had dead aga on my csppc/grex setup... be sure to use a GOOD psu!

[motrucker]

A good PSU is a good investment, for any machine! You are asking for trouble with the budget brand units. Bite the bullet and get a good PSU. I doubt if you will a 1Kw job, but I would go at least 600 watts.
I used to trust Antec, but lately I have had two 500 watt units die in quick succession! They made it good, but the trust is gone. ... Look for better.