Display problem

[kpilky]

hello all,i have a acer 3690 widescreen laptop.it has 100 gig hdd 1 gig of memory & intel mobile 945 family graphics.running xp media center original software that it came with it 15 moth ago.for the last few month it is booting up 4.3 instead of widescreen,sometimes it does boot widescreen but not often.the correct screen res is 1080x800 with these settings it boots ok but most times it boots 1024x768 that is 4.3 sreen.in display propertys the 1080x 800 is not there so i cannot change it.i have tryed different drivers but no change.i have uninstalled the accelerator driver & reinstalled it on reboot it comes up correct res & widescreen,i can restart & it boots up ok but if i shut down it's back to the 1024x786 res.i have a full clean reinstall & still the same.if any one can help me please it is doing my head in having widescreen & not able to use it thank you. Keith.