Error while rendering code: (7:66) - After Effects CS4

[m.sahlaa]

While I rendering my project in After Effect CS4, there was an error that says: unable to allocate space for 6000 x 5000 image buffer, that shown below: 

Then I try to follow the instruction to increase the RAM allocation (2.54 Gb free for other application) & Enable Disk Cache (I set max.5000MB) that shown below:

So, anyone can help me with this error problem? 

Thank you.