I have not had any trouble with any bios revision to date, I don't know what you mean by bios 1502 bricking boards, I don't believe that.
Red Jhon, are you over clocking your CPU, are you using XMP for you RAM settings, sorry I see you are running an overclock of 4.4, is this with XMP enabled and blck 125, most issues on the X99 platform are either RAM or USB related. If you were good on bios 1401 try flashing back. How long have you had those Velociraptor drives, I have had failures on the 150GB model myself and no longer use them. Do you have this problem with the non OS drives diconnected

Hello

The rare 1502 reported issue is most likely the result of an improper flash. This is also supported by the person that performed a second flash which resulted in the issue resolved as stated in the thread linked above.

Red Jhon, using USB BIOS Flashback flash back to 1401 if this version was problem free for you.

I'm sorry but I do not think it is a problem related to a bad bios flash.. I flashed this more than once and yet randomly keeps giving me blocks of code 95. With the 1401 bios does not have the problem of code 95 but only code AE / A3 caused by usb.

P.S. I always use the method Flashback

Did you download a fresh BIOS file or have you flashed the same file various times...sometimes a fresh file and a thorough clean of the pendrive work wonders...?

Open a command prompt window as Administrator and use diskpart to format your pendrive.
Best use a small USB 2.0 pendrive.

Type... and press enter after every line of course

diskpart
listdisk
select diskn (where n is the number of the pendrive)
clean
create partition primary
select partition 1
active
format fs=fat32 quick
assign
exit

But if it's not stable, of course, stay with previous BIOS for now....

Why rush into updating both copies of the dual-BIOS? Always keep the best/last problem-free version in one partition as something to fall back onto, only need to update the other. Just leapfrog between the two whenever a new BIOS comes out. Weird problems may not always manifest until after the machine appears to work perfectly for a long time, being able to quickly boot up the older BIOS can rule out (or confirm) BIOS-related issues. I have never personally irrecoverably bricked a motherboard from bad firmware flashing, I have never personally met anyone else who has either - it's not an impossible event, but it is a highly improbable one.

I wouldn't normally advise everyone rushing into routinely upgrading the firmware just because new firmware happens to be available. Not unless it specifically corrects some issue of importance or substantially improves compatibility or performance or capabilities. But as an R5E owner I always get sucked in, gotta try the latest-greatest and see if there's any truth to the claims that it's more better faster awesomer than ever before, so how could I discourage others from doing the same?

I still believe that Asus is horribly irresponsible in providing end users with absolutely zero BIOS documentation or version notes. Not even the briefest and vaguest of summaries. At best, regular visitors to these forums might see "unofficial" hints about what's eventually coming down the pipeline. We must blindly trust that newer must be better, that what Asus decides is best-for-everybody-else is also always best-for-us, and we must actually install/run the firmware updates to learn what's been changed. A little documentation would go a long way, I think, in informing people whether or not they should expect a particular BIOS version to resolve (or cause) issues of concern. Damned good thing our ROG mobos have multiple BIOS chips, if they didn't then I'd never dare to update (and maybe break) anything which already appears to be working well. That's a pretty weak position for a leading hardware manufacturer. It's affected my purchasing choices before, if left unchanged it will again.

the fast boot -sata is another documented issue that has been around for all BIOS releases but asus have yet again decided not to fix it.