Please note the below listed system requirements for DayZ:
Minimum:
OS: Windows XP or Windows Vista
Processor: Intel Core 2.4 GHz or AMD Dual-Core Athlon 2.5 GHz
Memory: 1GB
Graphics: Nvidia Geforce 8600GT or ATI Radeon 3650 or faster with Shader Model 3 and 512 MB VRAM
DirectX®: DirectX 9.0c
Hard Drive: 10 GB free space
Arma II: CO
Minimal PC Requirements
CPU: Dual Core Intel Pentium 4 3.0 GHz / Intel Core 2.0 GHz / AMD Athlon 3200+ or faster
RAM: 1 GB
Video Card: NVIDIA GeForce 7800 / ATI Radeon 1800 with Shader Model 3 and 256 MB VRAM or faster
OS: Windows XP
YES. You will be able to run it, albeit on low or even the lowest settings available. But the important thing is you will be able to run both the games, moreso Arma II as it is less demanding according to the system requirements.
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