I've just been looking at Tandberg Data's Q4 and full FY 2006 results. They are fascinating. Those kindly Norwegians have broken out backup sales by format. Here are some numbers for tape drive sales in Q4 2006:-

- DLT tape drive revenues were $2.3 million (down from $2.4 million in the year-ago Q4),
- SLR $5.5 million (down from $8.2 million),
- VXA $2 million (from zero in Q3 which was before the Exabyte acquisition)
- LTO $12.2 million (up from $8.1 million).

Both DLT and SLR drive revenues declined. LTO just bull-dozed ahead.

Tandberg started selling RDX ProStor removable disk product at the end of the third quarter. The RDX revenues? I thought you might ask. Here is the number:-

- $1.7 million.

How about that? Tandberg's statement said 'RDX: Successful qualification by OEM and introduction in the channel. Several thousand items sold in the fourth quarter." That number will be both for drives and media. Still... considering that VXA tape technology is mature it's surprising that RDX was anywhere near VXA revenue levels in its first quarter.

How many RDX drives were sold? My back-of-the-envelope calculation assumes an ASV of $700 for a drive and 3 disks which gives us 2,429 drives; it'll be in the 2,000 plus area I guess. That's pretty damn good.

Assume the RDX ramp continues. Then in Q2 or Q3 RDX revenues at Tandberg will exceed those from VXA drives and accelerate past the declining DLT drive revenues.

Dell is selling removable disk backup as well and it might have recorded double Tandberg's level of sales. That means (frantic guessing going on) 7,000 removable disk drives were sold in the last three months of 2006. Just maintaining that run-rate will mean 35,000 removable drives in customer sites by the end of the year. But it's likely the run-rate will accelerate - we need an IDC analyst to look at the figures and do projections - it could be that an installed base of 70,000 units will be achieved by year end.

Imation is developing its Odyssey and Ulysses removable disk format products. They might pile in to the D2RD (disk to removable disk) backup market in 2008 and the D2RD drive run rate could jump up again.

I know, one swallow doesn't make a summer, but $1.7 million in three months from a brand new product is pretty encouraging, especially against declining low-end tape sales. Buy your sun screen now. Go on, take a chance.