Is gzdoom on an amd card really 20x slower than nvidia?

Someone over on the zdoom forums said, for frozen time at least, the drawcalls on an amd card were 20x slower than nvidia. I have a radeon 290 and a geforce 760 in the same machine, but I'm a bit bummed out that I'll have to use the nvidia when all my other gaming uses the amd. Or is the problem just specific to the wad? I just want good performance on project brutality on slaughter wads.

PB gameplay doesn't support slaughter maps either way due to the much faster projectiles and larger variety of enemies and attacks.

rileymartin said:

PB gameplay doesn't support slaughter maps either way due to the much faster projectiles and larger variety of enemies and attacks.

How about plain brutal, or map 15 of ancient aliens that drops down to 25fps at 1920x1080 on my 4ghz i7-870 with geforce 560?

I run gzdoom with a Radeon R9 290 in 1080p and have had FPS problems on only the largest slaughtermaps (and then it was just slight stutter, like 50fps instead of 60 locked). I really don't think you need to use your Nvidia card, it should work just fine.

invictius said:

Someone over on the zdoom forums said, for frozen time at least, the drawcalls on an amd card were 20x slower than nvidia. I have a radeon 290 and a geforce 760 in the same machine, but I'm a bit bummed out that I'll have to use the nvidia when all my other gaming uses the amd. Or is the problem just specific to the wad? I just want good performance on project brutality on slaughter wads.

Yes, it is correct that draw calls are 20x slower on AMD.
But of course that does not mean that everything is 20x slower because running the game consists of other tasks as well. On large maps this difference can cause a performance difference of ca. 20-30%.

But you need something like Frozen Time for this to add up to some relevant amount of time.