Is sequential or parallel website image loading faster (using Javascript)

Question

I am currently scripting an AJAX image gallery of sorts, which preloads several large images (at least 120kB per image up to 2MB) before the lightbox is displayed. My question is whether to load these images sequentially (e. g. have the preloader wait for one image to preload at a time) or load the images parallel. My guess is, that multiple http connections (parallel caching) will be faster than a single http connection. However, I have read somewhere, that with the older IE had performance issues with parallel image loading. Is that still the case?

I am coding the entire project in XHTML5 (HTML5 XML) and will target only current stable releases of the most common browsers (Safari 5+, Chrome 15+, Firefox 8+, IE9+). AJAX'ing is done with the jQuery ‘framework’.

I am aware, that there are underlying network issues, which can greatly impact the loading of data (combinations of latency, bandwidth, connection quality in terms of packet loss, max allowed concurrent connections by isp, proxies, servers, etc.). Let's just assume that the average user will use a somewhat decent connection (dsl, cable, fiber) with a latency below 80 ms and a bandwidth greater than 6 Mbps.

Answer 1

parallel loading seems to be faster on most connections.