so i have a intel DP35DP mobo and a Nvidia GeForce 8400GS video card at the moment. I just bought a new monitor, Dell ST2410, and really want to use the HD and get some better graphics for some gaming. The problem is im really behind in my video card knowledge and cant figure out what is going to be compatible with all this pci, pcie, pcie 2.0, 4 pin, 6 pin, power supply stuff. A friend of mine recomended the Nvidia GeForce GTX260. I really like what i have read and his experience with it, but am afraid to order without knowing it would fit. My power supply is a Thermaltake TR2 RX-550. I dont have to get the GTX260 specifically and any suggestions are definately welcome. I want to try to stay under $225 at the most. Thanks in advance to everyone I really appreciate the help.