I spent some time today trying to diagnose a performance problem with Adobe Media Encoder CS4. One of the designers I work with had upgraded to Creative Suite 4 on an old PC and he quickly found that simple rendering tasks from Premiere Pro CS4 were now taking days to complete.
Most of the solutions on the web advise purchasing expensive hardware upgrades, but there is another workaround; the designer also had Adobe After Effects CS4 installed and it still uses its own render queue. All the Media Encoder render and compression options are available within this queue, but it performs much faster.
The clip we were trying to render took just two hours in After Effects, compared to an estimate of over 100 in Media Encoder. You can also send Premiere Pro projects to After Effects for rendering.