HD videos slow?

[Muz1234]

Why HD videos is slow in my computer? Low RAM? My CPU is 2.20 GHz, and RAM is 3 GB.

Here is the media info:
General
Complete name : H:\[C2.Lab] 02.RANKO\ranko 02 2160p.mp4
Format : MPEG-4
Format profile : JVT
Codec ID : avc1 (avc1/mp42)
File size : 2.57 GiB
Duration : 30 min 21 s
Overall bit rate mode : Variable
Overall bit rate : 12.1 Mb/s
Encoded date : UTC 2015-07-26 16:33:33
Tagged date : UTC 2015-07-26 16:33:33

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L5.1
Format settings : CABAC / 2 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference : 2 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 30 min 21 s
Bit rate mode : Variable
Bit rate : 12.0 Mb/s
Maximum bit rate : 17.0 Mb/s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 29.970 (30000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.048
Stream size : 2.54 GiB (99%)
Language : English
Encoded date : UTC 2015-07-26 16:33:33
Tagged date : UTC 2015-07-26 16:33:33
Codec configuration box : avcC

Audio
ID : 2
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Codec ID : mp4a-40-2
Duration : 30 min 21 s
Source duration : 30 min 21 s
Bit rate mode : Constant
Bit rate : 128 kb/s
Channel(s) : 6 channels
Channel layout : C L R Ls Rs LFE
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 SPF)
Compression mode : Lossy
Stream size : 27.8 MiB (1%)
Source stream size : 27.8 MiB (1%)
Language : English
Encoded date : UTC 2015-07-26 16:33:33
Tagged date : UTC 2015-07-26 16:33:33

 

[Supmop]

what can I say ??