Hi guys,I am upgrading again, this time getting probably a X1900.My concern is that my PC is powered by a 550W PSU, which, even though seems enough for anything, it is brandless and I don't really trust it much.Notheless I have a identical spare + another couple of 400W PSU.I would like to run the VC with one of the spares (only for the VC). How do I do that? Do I just plug the PCI connectors to the VC, turn the PSU switch on and with that I have power feeding the VC?BTW, just FYI I use my case open (the FX55 likes it that way better), so I would have the second PSU out of the PC.Thanks,Leo

Couldn't hurt. Never heard of it before, but a clean, dedicated feed for the graphics card is one of the holy grails of the overclocker, so I can't think why it wouldn't work. Won't look pretty, but should be alright.I've seen countless cases for 2 CPU's, 2 soundcards, even 2 motherbards and 2 graphics cards, but I don't think I've ever seen a case designed for 2 power supplies. You'll have to let us know how you get on as this could be a useful upgrade path for a power-hungry system, like we will need for FSX!Allcott

It is possible to run a 2nd power supply for the GPU, but... it is tricky and involves shortening the plug to make the PSU "think" that the power adapter to the mainboard is connected.Your 550W no-name brand PSU should be MORE than sufficient for your needs. Your mainboard should've come software to monitor the voltages and if you see that they're out of whack (~5%) then you should swap your power supply anyway.G'luck!Pat

I have done this before with two 250W power supplies before I lashed out and bought a 500W jobbie. Basically, the second PS needs a power on signal from the connnector that usually goes to the motherboard, otherwise it won't turn on. The following link gives you some options for setting up a second power supply: http://www.directron.com/2powersupplies.html#introSequence is very important, as your motherboard will get upset if any critical peripherals are not already powered up when does, so make sure you turn the secondary PS going to the video card on first, followed by your primary power supply feeding everything else. If you do it the other way around, the motherboard will think you haven't plugged power into the video card and will give error messages / beeps to tell you so.As others have stated in this thread, your 550W power supply should be enough as it is, so try your single power supply option first before messing with wires, switches, relays and electrickery.Gary

Yup..this is how you do it.http://forums.simflight.com/viewtopic.php?t=46811http://www.7volts.com/atx2.jpgConnect 14 and 15. in the cable thats supposed to go to the motherboard.ie. PS-ON and Ground (Green and Black)I have a paper clip bent and shoved it in. I don't have a permenant solution as yet.Try bending a paper clip to connect 14 and 15 and then turn the power on. It should power on.