I believe Cal is not correct strictly speaking, but is however correct in practical terms.
The signal degradation happens in the connector and along the length of the cable. If the cable used for both HD15 connector and BNC (on one end) interconnect is identical (as is sometimes the case), the cable length could not be a factor in deciding one vs the other.
The SVGA/XGA cables are NOT created equal though. The so-called VGA cables (thin) typicallu use twisted pairs for all the signals - the thinnest might perhaps even have a single common ground wire (or shield) shared by the signal lines. Some HD15 / HD15 cables connect all the pins by means of extra-thin mini-coax cables.This is not too good as the loss is significant. Others may have a combined design where the RGB lines (and perhaps the H & V Sync) are larger diameter coax, afforded by the remaining lines being twisted pair or non-existent.
In the BNC-outfitted cables, there's just 5 coax lines which sort of assures it will perform as well as a good coax+twisted pair HD15-HD15 cable.
If quality is critical you may invest in something like
http://www.cobaltcable.com/Merchant2...Code=dig_video
Otherwise look into
http://www.pccables.com/cgi-bin/orde...search=MONITOR
Alec