I've just replaced the motherboard on my computer and while it was all working fine at first after 2 days it's exhibiting some weird behaviour with my Microsoft USB Optical mouse. From a cold boot the mouse will not be recognised by Windows (neither Win98SE nor Win2000 - dual boot) will recognise the mouse and it doesn't light up fully - only very dimly as it is before windows loads. If after Windows has loaded I unplug and re-plug the mouse into the USB port then it lights up and Windows instantly sees the mouse. Exactly the same behaviour in both Win98 and Win2000. Subsequent warm boots / in and out of Stand by mode etc no problem. It's only from a cold boot that this happens. Is it likely to be a motherboard problem or is it just my mouse dying? Any ideas?