My suspicion is that this is more a browser issue that a server-side one. The main difference in rendering between pdf and html (used when viewing in CRM), is that each image is downloaded separately by the client when rendering in html. If you have a lot
of images in the report, you may get timeouts, or suffer from the number of concurrent connections the browser.
If using IE, you can try increasing the number of concurrent connections (see
https://msdn.microsoft.com/en-us/library/cc304129%28VS.85%29.aspx) to see if it makes a difference. Something else you could try is to split the report into pages, as SSRS will render each page at a time, so fewer images should need to be downloaded at
the same time.
If you sill have problems, I'd use a tool like Fiddler to try and identify why images aren't being downloaded
Microsoft CRM MVP - http://mscrmuk.blogspot.com/ http://www.excitation.co.uk
