Sumatra PDF is a free light weight PDF reader which can handle PDF, XPS, CBZ and CBR formats. It is having a very simple interface.
The portable version of Sumatra PDF reader is also available which will help you to carry the PDF reader in a USB drive.
Sumatra PDF is a slim, free, open-source PDF viewer for Windows. Sumatra has a minimalistic design but still has most of the features you need from a PDF viewer. It's small and starts up very fast.
I have opened same PDF file on Foxit Reader and Sumatra Portable PDF reader, you can see the memory usage below
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