The demo of Killzone: Shadow Fall shown during PlayStation 4's announcement only used 4GB of memory - not the full 8GB GDDR5 RAM available to developers in the final hardware, Guerrilla has revealed.

According to the studio, 3072MB (3GB) of PS4's 8GB were dedicated to video resources powering the demo, with 1,536MB used for system resources. A further 128MB were shared between the two.

Of the 3GB reserved for video memory, 1,321 MB were used by non-streaming textures.

According to Guerrilla, the demo featured 8200 physics objects, 500 particle systems and real-time reflections - which include "a lot of Guerrilla secret sauce".

Guerrilla's decision to stick with 4GB suggest that the developer may not have been aware of Sony's decision to include 8GB in final retail hardware - something Just Add Water CEO Stewart Gilray told had been kept secret from third-party developers until the console's announcement.

"We were told [PS4] was 4GB originally," Gilray told us, "and we first knew it had 8GBs when Mark said at the event's stage, 'And it has 8GB of memory.' We'd had kits at that point for a good while."

Killzone: Shadow Fall is due to launch alongside PS4 later this year.

Source: Guerrilla Games