My XFX 8800GT 512MB Alpha Dog Edition (Stock Clocks) runs on my Antec NeoHE 430W PSU that has three 12v rails at 16amps each. The card requires at least 26amps total on 12v rail(s) and at least 400W PSU.
Should I maybe wait for the HD4600 series or something? I highly doubt a 9.5" card would even fit into my pc since it would be sticking out into one of the hard drive slots.
Also, the card's cooler must be on the left side of the card if you lay the motherboard on the computercase/mobo on the ground and have the outputs (dvi, hdmi, sound, usb's, ethernet) facing backwards. If the cooler is on both sides of the card, then it won't fit either because then a piece on my mobo will interfere with installation of the card.
PS: what do you mean by the "Rails" and how do you measure/read how many amps they can draw?
This card is about 7" long, and I have about 9" total length from the one end of the case, to the tip of the one harddrive..... I supposed I could move the harddrive, but i hope the the card's cooler isn't massive like on the reference GTX280 cards.
MY psu is a Thame Star ATX 450. Here's what it says on the sticker:
(supposed to be a chart)
I hope the forum doesn't mess up the formatting. (the commas are space holders, they don't have any meaning)
That power supply only has 20 AMPS on one rail according to what you have listed as its specs, I doubt it would be enough to run the 3850, I cant be 100% sure but i personally would be looking at upgrading the PSU as well.
I can tell you for a fact that the 3850 wont fit unless you move the HDD. The sapphire version of the 3850 512 GDDR3 has a single slot solution that will fit in your case (if you move the HDD down).