The card
Two manufacturers have already announced the building of cards based on PhysX processors, Asus and BFG. Asus rapidly sent us a card that we used for this test.
Asus’ card is announced to have 256 MB of memory as compared to 128 MB for BFG’s. Asus informed us, however, that the amount of memory was reviewed to 128 MB “for strategic reasons”. We tried to know more and we noticed that memory was no longer indicated in Ageia’s latest control panels. We were told that their cards (at least the first batches) will have 256 MB of memory but that the additional 128 MB wouldn’t be used. Ageia has probably decided not to complicate things by supporting several quantities of memory.
The card is equipped with a Molex power connector because the PCI bus isn’t enough to power it. Maximum consumption is announced at 28 watts, but without test truly capable of saturating the card (and/or show us this), it is hard to evaluate this consumption in practice. The price should be around 300€.
Drivers
PhysX drivers include two parts, the driver itself and the API. The driver, in 1.0.1.0 version isn’t the most important part as it doesn’t really evolve with new versions. The important element is the API.
PhysX isn’t a chip that is really programmable. Developers won’t be able to write some sort of physx shader. The API shows several functions that can be utilised in a fixed way, which it then transforms into programs that the PPU can execute. Changes brought to this API can cause problems since some fixed functions can disappear or be replaced by others and their behaviour changed. Developers won’t use PhysX hardware API but a specific version of it.
Each PhysX driver, in addition to having a new API has all previous ones. Or it’s supposed to. This isn’t always the case because a developer can have based his work on a certain branch of the API, have found bugs and asked for a new revision of this branch. For example Bet on Soldier uses the 2.4.1 version, but the driver which includes it doesn’t feature the 2.3.3 used by Ghost Recon: Advanced Warfighter. During installation, the driver doesn’t add additional elements, it replaces everything. In other words, it isn’t possible to run these two games with the same driver and you have to change from one to the other. This isn’t very convenient. Fortunately, Ageia released a 2.4.2 version a few days ago that includes the 2.3.3 and 2.4.1. You have to use this one and refuse installation of versions available in games. This system seems difficult to manage in the long term and it’s probable that Ageia could review the API architecture. Why not include the API dll directly in the game?
Ageia’s control panel tells you which version of the API is installed, has a small demonstration to verify that the PPU is functional, a diagnostic tool and access to updates.
Test configuration:
- A8N32 Deluxe
- Athlon FX 55
- 2x 1024 MB Corsair (
CAS2)
- 7900 GTX
- Windows XP SP2
