BIOS A05

On my E6520 the current BIOS is A03. I have discovered some urgent BIOS updates but before I can run those I need to update to A05. Took me forever to find this update on the Dell website, it's not easily accessible from the Driver section for this particular laptop model. I found it through a thread on the forum and it was located on the American website. From doing a little bit of research, a BIOS update shouldn't take longer than a few short minutes. After half an hour of listening to the laptop humming and looking at a black screen I just killed the laptop. Thankfully the update did not seem to take place at all, but I was afraid I had damaged the CMOS somehow and a motherboard replacement would be in order. I don't really want to run the A05 update again in case it all goes wrong. How do i SAFELY update my BIOS without the fear of ruining my laptop? Or should i just forget about this update and carry on as normal seeing as my laptop functions? Any advice would be greatly appreciated!