Power consumption and crashes when scanning

[AlunS]

Hi,

I just bought a TBS6981 as a replacement for a Tevii S480 based on the many positive reviews on the net. The Tevii card is basically two USB tuners on the same card with some cobbled together USB bridge, and didn't come out of standby quickly enough, so I thought a 'proper' PCIe card like the TBS one would be a better option. Otherwise it works just fine, with no power consumption issues, it just needs a single floppy power connector and it's happy.

The TBS6981 seems to use a lot more power, but only when scanning and changing channels, and unless I do individual, single transponder scans, it crashes the PC seemingly due to some kind of power surge. My ASUS E35M1-I DELUXE has some kind of power surge detection (I don't know how it works) and it is this that shuts the machine down.

Now, I must admit that I only have a 60W (internal DC-DC) power supply that came with my case, but this works fine with the Tevii card, and using a power meter I can see that it consumes only 35-40W at most, so there should be no problems. In fact, even if I fit the TBS card and do a scan, I don't see any excessive power consumption, even when performing single scans.

I tried the card in my desktop system with a 'real' PCIe power connector connected and it works fine, so it must be power consumption related somehow.

I have a more powerful picoPSU (150W) on order, and I hope that this will solve the problem, but in the mean time can someone from TBS explain why this card seems to cause these problems when scanning, and what the actual power requirements of this card are?

By the way, can someone clean out the spam, in this forum .. it's getting out of hand!

[bob]

Hi,
Compare to other solutions of DVB card,TBS6981 consume little bit more power.But with 150W standard PC power,it should work good.
With my experience,most of scanning issues not relate with power consumption of 6981. You case seems rarely.
Regards!

[AlunS]

Hi bob,

I installed my new 150W power supply today and it now works 100% ! I don't really understand the reason why this makes so much difference, but it solved the problem anyway, and that is what is important. It does seem to get a bit warmer than my old Tevii card, but tunes a lot quicker which is good.

[subcore]

I installed my new 150W power supply today and it now works 100% !

Thank you, AlunS.
I just bought an Asus AT5IONT-I with an Antec ISK 300-65 and a TBS 6922 card, and I experience the exact same issue. As soon as Tvheadend (running under Ubuntu 10.04 LTS) starts scanning for services after locating Muxes, the system immediately shuts down.

At least now i know that i can remedy the situation by bying a stronger picopsu, but it means i have to shell out another 80€ or so and fit it inside the small space of the antec case...

this situation could have been easily prevented if TBS actually gave out information regarding the power requirements of these cards. then i would have bought a case with a stronger psu in the first place.

With my experience,most of scanning issues not relate with power consumption of 6981. You case seems rarely.

how else would you explain a sudden and complete power loss? as in, hard shutdown?
if it was software related one would expect a) that just the dvb application crashes, not the whole system, and b) to find something in the logs.

since other users also have trouble with the power supply in miniITX / Atom size systems, i suggest you re-evaluate your position on this and do your tests under these specific circumstances. your colleague "steven" hints in that thread that TBS apparently tests ITX/Atom boards for compatibility, but without the test environment and the conditions these tests were performed under, his statement "it is ok" is woefully insufficient information.

(btw, i assume "bob" and "steven" are actually TBS employees, but without their realnames or any hint on their userprofiles other than their membership in the Administrators group its hard to tell.)

low-power configurations are getting more and more efficient. 65/90W systems arent that rare anymore to justify his or your statement.