Thanks for your suggestions. I have removed the large chart and replaced it with multiple graphs (one for each channel). I have utilised a sample compressor VI with a ratio of 10/1 and a collector with a 1000 sample buffer, in this way I graph the same length of time I did with the 10000 sample chart but with 10th of the samples. The problem with this is that I loose the =91spikes=92 from the data so I have taken both the maximum and minimum values from the compressor and graph both for each channel (this also lets me see the spread or noise in the data). This is a little messy as I need to do this for every channel (up to 9) but I do get a substantial speed improvement (up from 7.5Hz to approximately 40Hz when recording 8 channels and higher with fewer channels). The other problem I have had is that the number of channels to be recorded changes from experiment to experiment and I cannot resize and reposition graphs at run time, so I have had to create 45 graphs and hide various ones depending on the number of channels to be acquired, very messy. The only problem that I currently have is that I can not grantee that the size of the plot area will remain constant throughout an experiment as auto-scaling needs to be on for all channels (except 1) and the changing limits alters the size of the plot area, i.e. the graphs no longer share the same x-axis sizes.
The other thing I will now for next time is not to get a P4.
