New monitor install and now slow start up

[ru1thirst]

Well my neighbor has an old Dell 2400 and she wanted a new monitor. I made a suggestion of a certain Acer 22" and now after I hooked it up, installed latest Acer drivers everything seemed go to go. However, now when you restart the machine or cold boot it up, it hangs for 3-5 minutes with just blinking _ in the corner of the screen and then starts up. When you go to device mgr, the monitor shows up as plug and play monitor. After the initial install and drivers, it did show Acer under monitor. Now if you just let the machine run or use it for 5 minutes or so, all of the sudden you will here the windows sound of "new hardware detected" and if you then go to device mgr, it shows the Acer Monitor and not the plug and play monitor.
My question is, I think the monitor and drivers are the hang up on the very slow boot up now and not sure why. And why is it detected as a plug and play after it finally starts up and then minutes later switches to the Acer detection?
XP sp2 machine by the way with 1.25 gb ram and no video card. On board video only and monitor hooked up via vga.
Any ideas?

 

[ru1thirst]

Follow up: Just checked the psu. Only 250 watt. So could this be the problem? She had a Dell 17" monitor and it was fine so would a 22" just be too much for a 250 watt psu and onboard video? Would this cause the very slow startup?
By the way, its not spyware of viruses. Like I said, starts up fine with previous smaller monitor.

 

[ru1thirst]

Nobody has come across this huh?
Just my luck.