6800 Ultra Power Supply Issue

[Deskstar]

I need to amend my previous post in this thread in which I had asserted that my 3 year old Antec (22a on 12v rail) was giving me Low Voltage Warnings for my 6800 Ultra. In fact, after changing out my memory and adding a coupld of case fans to reduce the various temps, I go no more power warnings and also have been able to increase my overclock from 3.0 to 3.4GHz on a P4 2.8c. I do thank MartinCracauer who said that he was running his 6800 Ultra on an 18a 12v rail. That gave me incentive to tweak my own system to see what was wrong.

Deskstar

 

[Tomahawk513]

Alright, well the rig is complete, and it works... barely lol! Actually, the other day, I just got an Nvidia error message saying that one of the GPUs weren't receiving enough power... slightly disturbing news :-( but I rewired my whole system, and I haven't gotten any more error messages, but it's likely that if I were to add another fan... heh, not someting I even like to think about. But for all intents and purposes, I have what I need, it works, and I'm happy, except SLI isn't working for me in Windows 2000... oh well, time to get XP I guess! Thanks everyone, your help and advice is greatly appreciated.

 

[sparkyclarky]

Originally posted by: CheesePoofs
It depends on whether that is a quality 550 watt power supply or a generic one. If its a generic one, ie one that came with your case, then i wouldn't trust it to run 2 ultras. If it is a quality one, ie from anted, enermax, fortron, ocz, etc, then it should run two ultras fine.

A generic 500 watt power supply is often worse than a quality 350 watt power supply.

Yeah, quality is key. A low quality PSU will have inflated wattage rankings (e.g. measure wattage at room temp, vs. actual operating temp).