Operating System: Windows Vista SP2 or Windows 7 SP1 or Windows 8 (both 32/64bit versions)
Processor: Intel Core2Quad Q8400 @ 2.6 GHz or AMD Athlon II X4 620 @ 2.6 GHz
RAM: 2 GB (4 GB recommended)
Video Card: Nvidia Geforce GTX 260 or AMD Radeon HD 4870 (512MB VRAM with shader Model 4.0 or higher)
DirectX 11: DirectX June 2010 Redistributable
Disk Space: 30 GB available space
Sound Card: DirectX Compatible Sound Card with latest drivers
Peripherals: Windows-Compatible keyboard and mouse required, optional controller (Xbox 360 Controller for Windows recommended)
Assassin's series in mostly cpu intensive - sector calculation, and many npc stuff. Your cpu is little faster than 2cores Pentiums Sandy Bridge so it would be able to run ACIV at low, only that gpu bothers me. Even if it will run don't expect more than 20-25fps in city on low details ;]
I dont think you can run it on low. I run it on 1366*768 and low on a radeon HD 6770M overclocked @840/920 and get an average fps of abt 32 fps. It is also backed up by a quad core i7. So, you have a remote possibility, though u can try at a lower resolution but all the beauty of the title is lost at anything lower than 768p.