tried everything to wake my i1400 - any other ideas ?

[oppositorum]

my i1400 thinkpad has, upon leaving it switched on for hours, fallen into deep hibernation. when turning it on, the cdrom is visited but no sounds of hard drive or fans. the battery light, the half moon light, and the Z in a circle light (on the far right) are all green. nothing on the screen. the front cd rom control panel is also in operation.

- problem's not the monitor - plugged another and still nothing
- tried removing the battery and powering
- tried holding the power switch down for 10+ seconds
- tried turning power on and off repeatedly
- tried function F4
- checked ram is tightly installed

can anyone offer another idea for what the problem might be ?

thankyou very much

jason