Well, having just seen Phil's Computer Lab video of Athlon systems and the 5v rail (SEEN HERE), I decided to give you guys the PSU information. I JUST tried that x700 GPU in the system with EVERYTHING unplugged except one stick of DDR-400 RAM. That means I unplugged the HDD, Zip drive, DVD-RW drive, both intake and exhaust fans, and even pulled 1 of my RAM sticks, the sound card, USB card, and network card. What we are left with is JUST the Abit KX7-333 motherboard, the AMD Athlon XP 3200+ Barton CPU, 1GB of DDR-400 (single stick), and the ATI Radeon x700 AGP card. It failed to POST with all three PSUs. Here they are for you to look at.
Cooler Master 500-watt
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An older PSU that used to run the Athlon XP system back in 2003 - plan to use it on my P54c 200MHz Retro gaming system
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My 2010 Kingwin 1000-watt PSU that powered my GTX 480 SLI rig on an i7-860 for 6 years
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Looks like I have 125 watts available on the +5v rail for both the Cooler Master and the older PSU, and a whopping 150 watts on the Kingwin PSU. I'm not counting the extra 25 Watts on the +5VSB there, because I don't know what that is.
Anyone thing I'm not feeding the system enough power to run the x700 with this? Phil?