title: How to allocate DMA Buffer of 500 MB in Windows XP
body: <p>There is a PCI card connected to the PC and we have a GUI for the same. We want to allocate DMA Buffer of about 400 to 600 MB physical memory in RAM in order to read/write from PCI Card (FPGA does Read/Write operation in PCI Card). We are using JUNGO windows PCI driver. There is a WDC_DMAContigBufLock method provided by JUNGO to allocate DMA Buffer through Contiguous or scatter/Gather Methods. We could able to create up to 63MB of buffer in the RAM and could not create more than 63MB. The operating system is Windows XP 32 bit and RAM size is 4GB (Relatively 3 GB is Free).</p>
  
  <p>Application (GUI) is written in C# .Net and trying to create a DMA buffer of 400 – 600MB is through this application. I am looking for solution/Ideas what could be causing/stopping me to create Buffer size of 400 - 600MB. </p>
  
  <p>Thanks</p>