How did you format the 640 GB HDD? I am not sure, so I am asking.

1) Put PS3 in standby mode

2) Hold power botton down to turn on, it will beep once, then beep again and turn off, release.

3) Hold power button down again to turn on until it double beeps, quickly remove finger.

4) PS3 will enter Recovery Mode. From there you can do a couple things, fifth option is to format hard drive.

After you format drive the PS3 will reboot, at which point it will ask you to hit select start to begin installing update from a USB drive to install onto HDD.

This is the part where it fails, after formatting completes and it starts to try and install the update to the 640GB drive.

Remember when Sony actually added features with a firmware upgrade, when was the last time that happend?

Weird 0_o

Thanks for explaining anyway. I see now what you mean. You can try to format the HDD some other way, like plugging it via USB to your PC and using a software to format it to fat32. And then just plugging it back on the PS3 and just turning your PS3 on.

Or you should try to download the update again? 

Its possible Sony fucked this update up for some HDDs. I can't see how though.

I know internet, grain of salt, but some guy on a (ahem) questionable forum was thinking it had to do with some specific buffer types.

I dunno either, I remember when I was first researching putting in a larger hard drive people were saying some drives wouldn't work.

I'm pretty sure sony did something that inadvertantly caused the drive to not be updateable. If I had just stuck with 3.55 it would have been fine.

Try reformatting your hard drive in windows. chkdsk is your friend...

Its possible that you have a small sector thats corrupted in your hard drive that is giving you the grief.  If you can repair it then try to format it in your ps3 it might work again.  Just a thought mate. 

Yes I was thinking of running a thorough disc check just in case. But i've already formatted fat32 -> ps3 -> fat32 -> ps3 a couple times to no avail. Last resort is to check for bad sectors or wait for next firmware.

If you have done all that you might as well go with the checkdisk just to be sure.  If not you can always wait like you said.  Either way good luck and hopefully that does the trick.

no, so ugly ..

http://www.gamepur.com/news/2615-ps3-firmware-update-356-hacked.html

KaKaRoToKs say..helo SONY ..

Even with the latest keys, people who update to 3.56 won't be able to install CFW.

They fixed their non-random random thing :)

Also, people updating from 3.55 CFW to 3.56 OFW will brick their consoles.

And... they banned a bunch of CoD:BO players.

Win for everyone! :D