Memory Leak in Play Mode

I use Unity 4.6 Beta for making my project. When I use it on Windows 7 32 bit (PC), I have no problems. But I need to work on my new laptop with Windows 8.1 64 bit, so I transferred the project (64 bit) there and I have a serious problem with memory. When I click Play, Unity slowly consumes more and more memory. It consumes almost 3 GB of memory ( I have 4 GB on my laptop). It lasts very long (an hour or more) to go into Play Mode. But it is happening only when I click Play for the first time, then it goes in Play Mode normally. When in Play Mode, the used memory is 500 MB memory only. It happens with all scenes in the project. My project is very big - about 80 GB.

I made an empty project and click Play. Unity goes into Play Mode quickly without problems. Is it possible that some of my assets makes this problem. And maybe the Unity Beta? But I don’t experience that on my Windows 7 where I use the same project and the same Unity.

After having transferred the project to my laptop, I rebuilt (reimported)the project three times - no improvements. No problem when Unity isn’t in Play Mode.

I wish to know if somebody has such a problem.

My computer details:

OS Name Microsoft Windows 8.1

System Manufacturer ASUSTeK COMPUTER INC.

System Model X551MA

System Type x64-based PC

Processor Intel(R) Pentium(R) CPU N3520 @ 2.16GHz, 2159 Mhz, 4 Core(s), 4 Logical Processor(s)

Name Intel(R) HD Graphics

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