I do video to >500k people per day and what you're planning with bankrupt you or have your hosting company shut your site down within days - most likely both.
As Antoine states you will have to use a dedicated server for this and you also need to discuss this level of bandwidth with your hosting company - they may be able to offer you a much better deal if you plan it with them.
Out of interest are you going to have a larger content pool than your cache/s? if not what's your disk random-read performance going to be like? If you were to somehow spread out your 5k load evenly over a 24 hours period (and that's REALLY not what will happen) that's still 4 x 1.6MB/sec you need to server...consistently...ever minute of every day...without jitter - quite a tall order for one or two SATA disks.
Oh and Antoine is right, 400MB for 4 minutes is almost exactly ten times the bit-rate I ship, are you sure it's right?