Performance hit for FSAA

[ArchAngel777]

I was curious if anyone happened to know the answer on this one. Take for instance the 2x2 SSAA mode, which is supposed to quadrouple the resolution from where it is set. So, if your resolution is set to 1280 X 800, it will sample it up to 2560 X 1600 internally, then output it back to the standard resolution. Keep in mind that I am not referring to MSAA, not even TSAA. I am talking about old school SSAA or FSAA. nHancer supports these old legacy modes to some extent.

So here is the question... What would get higher frame-rates, assuming both have the same video card.

1280 X 800 with SSAA 2X2

or

2560 X 1600 with no AA

?

It would seem to me that the performance would be very similar...

Anyone know?

 

[BFG10K]

It depends on the game and you'd really need to test the titles you play to see what the deal is.

It's generally not a good idea to use 2x2 as it tends to AA near horizontal and near vertical edges reasonably poorly due to its ordered grid. In most cases 4xMSAA (rotated grid) offers better IQ with a much lower performance hit.

 

[SonicIce]

Ditto.

Although, in theory, you would think 1280 X 800 with SSAA 2X2 would be slower because it needs to average the pixels together.

 

[Cheex]

Ditto.

Ditto.