AT power for ATX MB

[oldbob]

Have an unidentified motherboard with ALi Alladin V chipset. It has both AT and ATX power supply connections, but doesn't start with AT power supply (all Debug Sensor LEDs are lit, but no video and no FDD). Manual only mentions ATX PS connection and ignores AT connector.
Could it be that MB just won't operate with AT power?

[Ultima]

What mobo is it???
It should be printed in the manual or on the board itself.

I myself have a p5a-b which also has at and atx, but it doesn't matter what connection I use, it works fine all the time, so.....
Maybe there is a jumper on the board to switch from atx to at, I don't know??!!!

Pim

[oldbob]

I don't know, that's the problem. It says "5ABBA" for the model on the user's manual and the box says "FASTFAVE", but I can't find any such Mfr. The manual just gives the model and made-in-Taiwan -- no Mfr name or address. No identifiable model or mfr on mobo itself. It's a cheapie that I bought for the fact that its socket 7 and takes either SIMMs or SDRAM, to replace an older mobo and use existing components.
There is one other possibility, but I doubt this is an issue. The manual gives jumper settings for a 166mhz or faster Pentium or AMD, or a 133Mhz or faster Cyrix. I'm using a Pentium 133 CPU with jumpers set for 133/66 Mhz x 2.
Any ideas?

[Peter M]

You might well have to start it ONCE by shorting the Power Button connector - if this mainboard was connected to an ATX power supply before, it won't start on an AT PSU unless you do that, or reset CMOS contents altogether.

Regards, Peter

[Peter M]

... got to be more precise here. You are to short the Power Button connector ON THE MAINBOARD, _not_ the AT PSU power button.

Regards, Peter

[Ultima]

I have seen mobo's with both power connection and some of them had a jumper on the board itself with which to set the connector favor.

I have a 5agm2 from chaintech which has this feature.

Pim

[oldbob]

Tried Peter Missel's suggestion. It sure sounded good but, that wasn't it.
BTW there is no power switch connection on this mobo. There's a LED connection for power on/off but the only power switch I have is between PS and mobo. I reset BIOS but that didn't do it either.
Took mobo back to vendor. He gave me new one no-questions-asked. He also said they use this board with AT power supplies all the time. I suspect bad board.
Will post results after I try replacement.