Vu flush to zero

[antipunt]

heey...sry I'm sure this insults the intelligence of many of you here, but can someone explain to me exactly what VU FLUSH TO ZERO is, and where it can be found? I'm at a loss here..

(was told that it speeds up many games)

[morpha]

AFAIK what it means is the CPU will simply flush values of floating point operations to zero if they'd require higher precision than the CPU's full precision can represent. So basically if an underflow occures, no further calculation is performed and a zero is returned instead since the value is very close to zero anyway.

That's how I interpret the information I could find on it, no idea if it's correct.

[kabooz]

options -> advanced
on the right side are the VU rec options

[antipunt]

thank you!

PS: this just a little aside, but can anyone confirm that Persona 4 (if you've played it) gets an FPS boost by enabling this option?

[bigmehdi]

@antipunt
anyway you won't get any slow down, so unless you are encountering problems , just enable it (and denormals are zero too)

[cottonvibes]

official build's have flush to zero ON by default; we made it OFF by default to increase compatibility (even though it might be slower)

as already mentioned, you can turn it on by going to "Advanced Options" and clicking the "Flush to Zero" checkbox for the VUs.

[antipunt]

"official build's have flush to zero ON by default"

thank you! that bout nails it