ouch....TCCD's dont like voltage dude...I would never go above 3v and if you're using 3v then you need to have a fan blowing on them...which patriots do you have? I have the XBLKs and those are rated at 250MHz with 2.5-3-3-7-1T timings and 2.85-2.95v, which looking at your timings, looks like you were going for the 266MHz which is rated at 3-4-4-8-1T at 2.95v...I think if you change it to 2T you can use 3-3-3-8 timings and go much higher (2T = Making CPC Disabled in the DRAM options)
About how long should I let it run to get a good idea of stability? At 15 min now.
12+ hours in prime95 when you're at a speed that you think you want to keep as 24/7....generally when I'm just trying to get past speeds I know it should take easily I boot into windows...run prime95 for about 5-10 mins and assuming it still passes I go back into the BIOS and bump it up another 5MHz....I keept doing that until it fails prime95 immediately at which time I give it a bit more juice