Hello all, I am hoping that someone can help me with some advice on this one, My Sony laptop will not start up at all, all that happens is the power light comes on and the hard drive light comes on for about 5 seconds, I also have three lights stay on the top right hand side of keyboard, no life to the screen at all, the hard drive I can hear whirring away and I have power to the DVD drive, first I originally had a graphics problem with artefacts all over the screen that then progressed into this state with no life at all, so I bought a tested second hand mother board, and fitted it but same problem, I have removed the hard drive the ram DVD drive and removed the bios battery for 30 min's and still nothing, I have also re-seated the T5600 processor and still nothing, I am thinking that it might be either a corrupt bios (but removing the batt should reset this I thought) or a main T5600 processor chip, I anyone can offer something it would be really appreciated, thank you.

assuming you have tried to get into the bios by pressing the (del, or F1, or whatever) if you can get into the bios check to see that all is well, ie it knows about the hard disk.
If you cant get into the bios have you tried starting up with a recovery disk or a linux boot disk?
Have you tried putting an external monitor onto he rear of the machine as it could be a screen problem...
do you get any 'beeps' as it tries to start as those can often tell you a bit more about why it wont work. However it does sound like a problem with either screen or the booting of the HD


Thanks for the reply, i have tried del f1 and all sorts of combinations and still nothing, i don't have a recovery disk, and I'm not sure where to get a Linux boot CD from, i have tried an external monitor and still nothing, all i am getting is the hard drive led on for about 3 seconds and thats about it, dead screen on the lappy and on the external, i have tried hitting function f1 on everything and nothing, i have no beeps at all, i was wondering will a laptop still boot up without the hard drive fitted and or no rams fitted, cheers.

all computers start up by
1. processor first (it checks itself and on modern machines will vocally or continuous beep tell you if it is NOT ok.
then ther is the POST check where the processor checks to see if there is keyboard, monitor, memory, hard disk etc. Normally it doesnt beep but if it does hte number of bee"ps indicates the problem aqrea (varies with dfferent bios);
3 memory check and if all ok then
4 it looks for a device to boot up from. the order of which device to use first is in the bios and can be changed. hence if you remove the hard disk it can boot BUT ONLY if there is a device to boot from such as a recovery disk or from a linux disk or from a bootable usb key. All the settings for this are in the cmos so in answer to your question a computer can boot from a device other than a hard disk but only if the bios tells it to do so.
Regretably I think your problem is either the MBR master boot record on the hard disk being corrupt (either by virus or by disk crash or by motherboard chip failure!!) and there not being anothr bootable device available (or hard disk failure) or it could be a motherboard fault (in that case you need more expert electronic skills!
cant help any more