Since you have a shop am i right you can swap parts in and out of compatable machines?
You have swapped the ram into a compatable machine and is ok is this correct?
You have swapped the processor into a compatable machine and is ok is this correct?
Have used a new good known working graphics card that is compatable in the affected machine still no change.
You have used a known good monitor and are getting no signal or please check signal cable?
Check fuse and wiring in plug of psu change fuse.
Check voltage setting on back of psu is set correctly if psu has the switch.
Change vga cable to eliminate faulty or damaged cable.
Try a different psu which is the same power rating as current psu see if it boots.
As for cmos battey remove and leave out for 1 minute with power off and disconnected. Replace battery should reset bios to default so onboard graphics will be enabled by default.
Minimal boot processor, 1 stick of ram and onboard graphics only, no nic cards, hard drives , dvd drives or usb front panels or pci devices etc connected to motherboard.
If resetting cmos fails could indicate bios corruption or a failure of motherboard which may indicate replacement needed. You can flash the bios go to motherboard manufacturers website there will be instructions, or if a brand name computer go to their website there may be special instructions for that particular model.
Just need to do the process of elimination first.
Hope this helps.
Edited by Darth sidious, 08 May 2010 - 09:02 AM.
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