I did succeded in upgrading a Philips DVDR HDD.
My model is Philips DVDR 3440 H.
I just took an empty IDE HDD (250GB) and I've installed into the recorder.
I set cable select, just like the original.
When I turned on the recorder nothing happed for at least 1 minute. No message on the TV screen (just the empty background).
On its screen there was a message but I didn't noticed.
After one minute, the disc tray was opened and on DVDR screen (not tv screen) appeared: "LOAD".
So I took the latest firmware from the www.philips.com (some zip file) and wrote on a CD.
Here is the list of the files:
19/10/2007 17:47 952,320 PHILIPS_51050224.BIN
26/12/2007 14:54 530,432 PS3440H_EUF.CUB
26/12/2007 14:54 7,507,680 PS3440H_EUH.CUB
26/12/2007 15:29 530,432 PS3440H_K_EUF.CUB
26/12/2007 15:29 7,507,696 PS3440H_K_EUH.CUB
ISO9660 + Joliet
I puted the CD on the tray and closed the tray.
After about five minutes, after 3-4 automatic restarts, the DVDR returned to life.
When I checked the HDD capacity: surprise: 250.000 MB!
The remaining available space was somehow displayed wrong, but after restart, everithing was just fine!
It is working and from now on I have 250GB available.
Try with yours too.