Samsung RC512 laptop won't boot up

I'm trying to fix a Samsung RC512 laptop that won't boot up. When I start it, the screen lights up with a top-left cursor that flashes twice, then the screen dies for 3 seconds, then re-lights, the cursor flashes twice, repeat.

When I forced a shutdown and restarted, pressing F2 for the BIOS app, the Boot Priority had been set to SATA CD first, SATA HDD second. There's nothing in the CD drive, so I changed the order to HDD first, but I get the same symptoms.

I tried F4, the Samsung system recovery, but that made no change. (Oddly, I got no prompt to confirm I wanted to delete all installed apps, or I wouldn't have approved that.

Does this look to you to be a hardware problem, or is there anything else I can do with the software to fix this?

 

Thanks for a quick reply, Evan. I tried F8 on startup, both pressing it repeatedly and just holding it down, but that was ignored. Safe Mode or Last Known Good Configuration aren't available; just the same symptoms happen. I haven't a Win7 disk, unfortunately.