Early Z Confusion with NV25 and the new Drivers

A

aths

Newcomer
Since 42.01, at least up to 44.03, Early Z can be activated with an Registry-Entry (D3D_48484658 set to 0x91256712) and be confirmed with an Overdraw-Test-Benchmark. By default, Early Z Occlusion seems to be disabled. But Villagemark shows by default full Early-Z-Performance. With explicit deactivation auf Early Z, (set to 0x91302489) Villagemark losts serious performance, also the overdraw-testers show no more any Z-occlusion.

I tested with 44.03 an UT2003-Timedemo, also 3DMark2000 and 2001 to confirm, that Early Z raises the performane (a little bit.)

Now with 45.23, this Entry seems to be ignored. The speed of Villagemark is as high as with Early Z, but all overdraw-Testers dont show any working Z-occlusion.

WTF is up with Early Z on NV25?
 
If there isn't a lot of overdraw and the shaders are simple Early Z can actually hurt you.
 
There is always overdraw, and the shaders tend to become more complex...

I don't understand, why Villagemark gets Early Z by default, even in 45.23, where it cannot be explicit activated. I tried it with 44.03 and Unwinders Cheat-Blocker, Villagemarks seems not be detected by the driver.
 
ERP said:
If there isn't a lot of overdraw and the shaders are simple Early Z can actually hurt you.
Click to expand...
I like to point out that this depends on the implementation and isn't a general rule. I don't know if it applies to NV25 though.
 
3dcgi said:
ERP said:
If there isn't a lot of overdraw and the shaders are simple Early Z can actually hurt you.
Click to expand...
I like to point out that this depends on the implementation and isn't a general rule. I don't know if it applies to NV25 though.
Click to expand...

Agreed in general it needn't, but I was makeing a statement about NV25 specifically.
 
ERP said:
Agreed in general it needn't, but I was makeing a statement about NV25 specifically.
Click to expand...
The NV25 can get a great boost with Early Z under certain circumstances. I dont know why NV disabled it.
 
aths said:
ERP said:
Agreed in general it needn't, but I was makeing a statement about NV25 specifically.
Click to expand...
The NV25 can get a great boost with Early Z under certain circumstances. I dont know why NV disabled it.
Click to expand...

<cynic mode on>
To make NV3x look decent in comparison.
</cynic mode off>
 
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