New monitor hangs in sleep mode after reboot.

The other day I upgraded my monitor from a 17-inch Dell LCD, to a Samsung 2053BW 20" Widescreen Monitor. When it came I just unplugged my old and plugged in the new one everything came up fine, I had to change the res. from 1024x768 but other than that it was perfect. Then today I restarted my computer for the first time since I got the new monitor, the BIOS load screen and Windows XP loading screen all came up like normal then when the windows log-in page should of came up the monitor just goes black and the blue 'on' light blinks like its in sleep mode. If I unplug the DVI cable for it from my video card and plug it right back in the screen comes on like it normally should. Is there a simple fix for this? I'd prefer to not have to keep plugging/unplugging that cable from my video card everytime.