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A Home-built Video Disk Recorder

When building your own vdr you will have to make choices. Some of the requirements are contradictory, some of the choices difficult. This page reflects the choices I've made. The main criterion was keeping the PC quiet. Keeping a PC quiet implies keeping it cool, as fans are a major noise source. Surprisingly enough, the main source of heat is not the CPU but the DVB tuner cards. Each tuner card dissipates up to 8W. In general, the more recent tuner designs consume less than older ones.




The cpu used is a socket 478 Celeron 2.0 GHz, C1 stepping. Chosen because the worst-case heat dissipation of 52.8W - what Intel calls Processor Thermal Design Power - vs. clock frequency compares favourably with other models.
When watching TV the CPU is 90% idle; CPU temperature reaches 37ºC at an ambient temperature of 21ºC and a fan speed of 1000 rpm. Maximum temperature is about 45ºC, fan running at 1400 rpm.
A 2 GHz Celeron CPU is too slow to watch HDTV. A 3 GHz Pentium IV with hyperthreading is quite capable of showing HDTV in real time, but generates so much heat fan noise becomes a nuisance. YMMV.



The CPU cooler is an Arctic Cooling Super Silent 4 Ultra. Reasonably quiet; does its job.

To slow down the CPU fan a temperature-dependent speed control from noisemagic.de was added.
Fan speed control


PC2100 stick
Memory is 256 mb PC2100 ram. You need enough memory to avoid any swapping, and 256 mb is just about right.
If you wish to run all user programs from a ram disk you might want to double this to 512 mb ram. Running user programs from a ram disk allows you to spin down the hard disk when not recording or watching recordings. Spinning down the hard disk lowers noise.



Intel D865GLC motherboard
Motherboard is an Intel D865GLC micro-ATX motherboard. This is a fairly conservative choice, as I wanted a board that followed the PCI spec exactly.
The motherboard allows for mounting the PCI cards vertically; this increases system height but makes convection cooling easier.


AGP card

Putting a hugely powerful video card in your vdr is probably quite unnecessary. Let's consider two setups: a classic vdr setup and a more modern one.

You cannot use every AGP card in every AGP slot; before buying check compatibility. My personal choice is an Aopen FX5200-DV256, a fully passively cooled nVidia card. No fan, no noise.


Hard disk

Hard Disk

Hard disk is a 250 Gb Samsung HA250JC SpinPoint. Disk size determines how many hours of movies you can store. A handy rule of thumb is that one hour of standard definition TV needs more or less one gigabyte of disk space. Hence, 250 Gb corresponds to more than ten days of uninterrupted movie-watching.
This disk spins at only 5400 rpm, but I neither need nor want a faster disk: I prefer a quiet disk to a fast one. High disk speed adds nothing to viewing pleasure.

DVD drive

DVD drive

A DVD drive for watching the occasional DVD or Video CD. Choose a quiet one.

Power Supply

Seasonic power supply

Power supply is a Seasonic 200SFD with temperature-controlled fan. Again, this is chosen with noise levels in mind.

Infrared receiver and wake-up board

Wake-up board

In addition to a LIRC remote control receiver you also want to switch the PC on by remote control. I'm using a ready-made microcontroller board bought from k-data (info at nospam.k-data.org) running software from Frank Jepsen. The board contains a small real-time clock that automatically switches the pc on when a TV programme needs recording. Unfortunately, documentation is only available in German.

DVB cards

Before buying a card it's probably not a bad idea to take a look at the supported hardware list in the linuxtv project. Even so, I suggest sticking to the most commonly used hardware: not all cards are equally well supported. A classical vdr setup is one with a single full-featured DVB card, possibly extended with multiple budget DVB-cards. The setup I'm using consists of two terrestrial DVB-T and one satellite DVB-S tuner. This fills all motherboard PCI slots.

Full-featured DVB-T

Full-featured DVB-T

Full-featured Technotrend DVB-T. On-board DSP memory was increased from 2 mb to 4 mb by Wolfsoft; and a small circuit board was made to provide a SCART output. Note that this is an already aging design; the DVB-T tuner is not very sensitive when compared to the "budget" DVB-T card. Not recommended for new systems.

Budget DVB-T

Budget DVB-T

Technotrend DVB-T. The tuner of the "budget" card is a lot more sensitive than the tuner of the full-featured card.

Budget DVB-S

Budget DVB-S

Technotrend DVB-S.
All DVB cards were bought from dvbshop.

The local TV stations all schedule movies more or less at the same time. Having multiple tuners allows recording multiple programmes at the same time. Recording four movies simultaneously is not unusual. Six simultaneous recordings is feasible, but then the system becomes sluggish. Commercials are removed later using noad.

Should you be interested in USB DVB tuners, please note that USB 1.0 and 1.1 designs have only limited bandwidth, adequate for a single SDTV channel only. USB 2.0 tuners are a better choice; they're fast enough to record multiple SDTV channels in parallel - if the SDTV channels all use the same frequency.

The satellite dish is a a 90 cm aluminium offset dish Triax TDA88 / Flexibloc with dual Alps LNB's for Astra 19.2º and Eutelsat Hotbird 13º satellites. Channels I actually receive are:

Satellite channels received

TV Radio
Free to air 764 757
Encrypted 933 140

A few transponders are missing because I'm not exactly in the center of their beams.


Klaus Schmidinger's vdr running on top of a 2.6 linux kernel. lirc is used for the remote control.


Lian-Li PC9300
The case is a Lian Li PC-9300 Micro-ATX enclosure. A Lian Li C01-A aluminium CD drive door was glued into place with silicone rubber. The lid, which covers case top and sides, was removed and replaced with a stainless steel mesh bought at a local hobby store. The open mesh allows convection cooling. More pictures.

Last update page: September 1, 2005