I have a HTPC going into the 990. From the 990 to my projector is a 30ft DVI run to my JVC HX2 projector. I am running the HTPC at a pixel perfect reolution of 1400x788 to my projector.

My problem is that when I run the HTPC through the 990's switch, it introduces these blue sparklies on the screen....and the longer it runs through the 990 the worse the sparklies get.

To make sure it is the 990 introducing the sparklies, I have tried different cables to no avail.... and also I ran the HTPC directly to the projector using the 30ft run and it gives a solid picture with no sparklies.

Is there anything else I can try? The 990 works fine on all other sources, like my oppo dvd player and my moto hd cable box. Is there a limitation on the resolution (or freq, sync polarity, sinc width, bp, fp) that can be fed to the 990? I am using exact resolution data from JVC to dial in the pixel perfect picture. I know I have read that the 990 is only a switch and should not introduce any artifcating, but I think it is a problem in my case.

Thanks for any help.

Lou

Lou Corsino

A 30' DVI cable is twice as long as the DVI standard allows for; I suspect that's the underlying culprit in the mix, although the added complexity of a switch in the signal path is apparently exascerbating the problem. The "sparklies" you describe are commonly associated with cable issues (in fact, I saw this very issue mentioned in association with Anthem's processor development in this HDMI cable review .

Thats the first thing I thought of but there are absolutely no artifacts or sparklies when I go from HTPC to Projector with the 30 ft run. Apparently something is being done or maybe just the signal is weakened in the switch when i run the htpc through the 990?

The cable I am using is actually a HDMI cable with Monster HDMI to DVI converters on both ends.

I might have to buy an outboard switch and see if it happens with another switch. I only have one DVI input on my projector so i need to be able to switch between sources reliably. Before I buy a switch I want to make sure there is nothing wrong with my 990.

If I understand correctly, the DVI switching on the 990 works correctly with the Moto cable box and Oppo, but not when connected to the HTPC?

If the first two work but not the third, then it would seem that everything is working and that no one component, itself, is causing the problem. Rather, it has to be something in the combination of the cable length and the signal output by the HTPC.

Well, it certainly wouldn't hurt matters any to give Outlaw a call or e-mail to get them in the loop on the issue. Do you use the HDMI-DVI converters when runnings straight from the HTPC to the projector?

Podboy -
I think I eliminated a potential cable length factor and signal output problem buy running the HTPC directly to the projector with no sparklies. As soon as I put the 990 between the two...I get sparklies. The only other cable it could be is the one that I run from the HTPC to the 990. I tried using two different cables (1 m each) and both produced the same results. The cables work fine with all my other DVI sources and the 990.

gonk -
I will email outlaw to see if they have any ideas. And yes, I did use the HDMI-DVI converters when running straight from the HTPC to the projector.

Thanks for responding...

Lou

Sorry we couldn't offer more. One thing that may be necessary with the cable length and a switcher (whether the 990's internal switching or an external box from somebody like Gefen) is a signal booster, but if you're like me you're keeping that as a last resort.

exactly...

thanks...i'll see what outlaw has to say...if anything significant comes out of it...I will post the update here.

I would recommend the cable from Ethereal availiable from Digital Connections. It is much fatter and as anyone familiar with loss in cables, loss is inversely proportional to volume so a big fat cable will be lower loss than a skinny one. They are selling them for $109. I am using it althogh I am not driving it with the 990 but with the 1 in 2 out amplifer that they sell. My projector is old and I find this solved another problem I had but it may also help drive the long cable.

Well, "big and fat" doesn't always mean what you think. For example, a lot of "big and fat" speaker cable simply has a thicker jacket (cough Monster Cable cough). 30' is a LONG way for a DVI cable without an inline signal booster.

Cheers,

I am using this cable between my HTPC and the 990. http://www.digitalconnection.com/products/cables/ixos_dvi.asp

And I am using this cable between my 990 and the projector

http://www.ramelectronics.net/html/DVI-hdmi_cables.html#hdmi-r2


Ritz - Would an inline signal booster be needed ifit works fine HTPC to projector for that distance? Does the 990 switch degrade the signal enough that it would have to be boosted out of the 990 to go 30 ft?

Keep in mind that you're exceeding the DVI spec for length by a factor of two (the spec only guarantees cable runs up to 5 meters) - although very low resistance cables can get you farther, anything extra in the signal path creates the potential for sparklies. Straight from HTPC to projector is as clean a path as you can get, but toss in an extra meter of cable from HTPC to 990 and the connectors and short conductors inside the 990's switching section and that may be enough to push you over the edge. It's an unfortunate limitation in the DVI standard (presumably due to DVI's original market of PC monitors, where you were not likely to go more than a meter or two). Outlaw may have some suggestions I don't know about, but you may have to look at a signal booster to use any sort of DVI switch with your projector.

I started a support ticket and steve asked me to call him when i get a chance to discuss the problem. I'll keep you updated.

I probably wont be able to call until thursday.

thanks for your help.

I still havent had a chance to call stve at outlaw...but... I think the problem is with the long cable. I threw in Citizen Kane and I saw sparkles...very hard to notice but noticeable nonetheless. This is with the dvi straight from htpc to the projector. So I think the 990 adds just a bit more resistance and causes the massive sparkling.

So, Does anybody have any suggestions on inline DVI signal boosters? I think I will try this to see if it fixes the problem.

Is this what i would need?

http://sewelldirect.com/Gefen-DVI-Booster.asp

thanks for any help

Or should I go with the super booster?

http://sewelldirect.com/Gefen-DVI-Super-Booster.asp

It looks like this one plugs in where the other one doesnt.

Just wanted to post a status update....I purchased the Gefen DVI Super Booster and it solved my sparklies problem. Going through the Outlaw must have had just enought effect on the signal that it caused significant sparklies and barely any when going straight to the projector. But now with the super booster I get a nice clean picture when going through the 990 and a 30 ft DVI run to the projector.

Thanks for all your help.

Glad to hear you got it sorted out.