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Topic: PCI-E Extenders all bad? Lots of problems. (Read 10954 times)

newbie
Activity: 43
Merit: 0
April 12, 2013, 04:19:23 AM
#32
Got a http://www.amazon.com/gp/product/B004XD74MC for $9 and it works perfectly... excepting that every time I restart my computer it only displays a blinking dos curser and doesn't start up unless I replug it in. But its those little quirks and flaws that keep a guy interested!
member
Activity: 98
Merit: 10
Mine hard!
I've got an Asus P5B-Deluxe (LGA 775 with 2x PCI-e X16). Can I add a riser and newer card to this? I'm thinking I can add two! Smiley
full member
Activity: 235
Merit: 100
October 02, 2011, 10:23:12 PM
#30
I wrapped between them (and then around), but it's most important that you wrap around them to keep external EMI out.

I wrapped around 2 of them then i came across the idea to wrap between them
so i thought i would ask.
unfortunately I'm now to inebriated to do the task on hand...
so it will have to wait till tomorrow
hero member
Activity: 642
Merit: 500
October 02, 2011, 09:04:34 PM
#29
I wrapped between them (and then around), but it's most important that you wrap around them to keep external EMI out.
full member
Activity: 235
Merit: 100
October 02, 2011, 07:31:03 PM
#28
Quick Question...
when I wrap the PCIE cables with metal tape...
do I wrap them up with a layer in between the cables?
or just around them?
hero member
Activity: 642
Merit: 500
September 29, 2011, 10:14:42 PM
#27
when i reset up my miners i'll be putting on the tape to make sure all is good.
curretnly i have each cable seperated by a piece of wood so that they don't touch
A piece of wood between each cable is enough to block EMI at those frequencies...  However, that would only block EMI between cables.  If there's nothing else near the cables, you're probably fine.  My problems were more pronounced because a lot of my miners had extenders running between cards that were physically plugged into the board.  However, I've experienced this problem on a rig with 4 cards *all* on risers.  They probably got their EMI from each other's riser cables being close to each other.  The tape took care of it though.
full member
Activity: 235
Merit: 100
September 28, 2011, 09:45:28 PM
#26
I'll be moving my rigs to the other side of the room this weekend...
going to vent all the hot air into the cold air duct instead of outside

[edit] had a power failur and just wanted to save this post before PC died...
anyways...
when i reset up my miners i'll be putting on the tape to make sure all is good.
curretnly i have each cable seperated by a piece of wood so that they don't touch
hero member
Activity: 642
Merit: 500
September 27, 2011, 11:08:45 PM
#25
In 3 months I have had no problems with my 9mart x16 extenders.  Currently I am using 8 of the 10 I bought.  I added Molex power to a couple of them myself since I am running 5 cards/rig.  Once or twice there was an issue with the miner not starting but it was because I had bumped a cable, re-seating the connector solved the problem both times.  Be careful that your cables are not rubbing on the PCB of the neighboring video card, I can see that as being an EMI source as well as a potential short if the fan vibration/heat wears through the insulation.
I haven't had any problems with the x16 extenders...  only the x1.  I have six 9mart x16 extenders and they have been just fine.  I'm guessing with PCI-E's ECC and the additional bandwidth through the cable, it's able to deal with the interference.  Just a guess though.  I've only had to worry about wrapping my 1x extenders, and I've had to do it with every rig to prevent the random miner hangs.
full member
Activity: 210
Merit: 100
September 21, 2011, 12:42:45 AM
#24
In 3 months I have had no problems with my 9mart x16 extenders.  Currently I am using 8 of the 10 I bought.  I added Molex power to a couple of them myself since I am running 5 cards/rig.  Once or twice there was an issue with the miner not starting but it was because I had bumped a cable, re-seating the connector solved the problem both times.  Be careful that your cables are not rubbing on the PCB of the neighboring video card, I can see that as being an EMI source as well as a potential short if the fan vibration/heat wears through the insulation.
sr. member
Activity: 322
Merit: 250
September 20, 2011, 08:06:34 AM
#23
I forgot to post this quite a while back, but I should have.  I'm surprised that I haven't heard this mentioned anywhere else, but I had a similar problem that took a little time to figure out.

Backstory -- When I first started putting together my first mining rigs, I noticed that some cards were performing slightly better than others.  Card performance varied anywhere from 1 to 4 percent.  It didn't make any sense.  I had 32 identical cards that had the same clock rates, so the performance should be nearly identical between cards.  At the time, I was using separate instances of Phoenix for each card instead of a combined miner, so I could see the hash rate discrepancies.

Long story short, I noticed that the cards connected directly to the board never varied...  only the cards with 1x risers did.  My rigs have 4 cards each -- 2 in the board and 2 connected with risers.  I then noticed that the hash rate in Phoenix would fluctuate when I moved the riser cable around.  Yep...  the risers easily pick up EMI from nearby components.

Since PCI Express runs at such a high frequency, it's extremely susceptible to interference over long distances.  You'll notice that most of the "name brand" risers are shielded (like this one http://www.newegg.com/Product/Product.aspx?Item=N82E16815158290).  They're shielded for a reason.

With every miner I assembled, I sat and watched Phoenix while moving the cable around until I hit the max hash rate (and then left them there).  However, I had cards that would stop mining randomly.  Sometimes they would mine for a few hours, sometimes 1/2 of a day, and sometimes days without hanging.  When they would hang, it didn't take anything more than restarting the miner.

I started logging these hangs over the course of a week or so.  I noted which machines would hang and which cards it happened to.  Of course, it always happened to the cards with the risers.

Here's what I did to fix it.  I bought a roll of aluminum duct tape and shielded the cables myself.  Be very careful with this though -- aluminum is very conductive.  If you're afraid of them touching against your components *wrap them in electrical tape* after applying the aluminum tape.  I'm sure you could use aluminum foil to shield them too, but I'd recommend the tape if you have very many risers to wrap.

After doing this, I *rarely* get a miner that hangs.  With 54 video cards mining 24/7, I only have to restart a miner about once every week or two.  It rarely happens.  Here's the exact tape that I used, but I'm sure that just about any aluminum foil will do the job.  http://www.amazon.com/Nashua-324A-Cold-Weather-Premium/dp/B0015V93KG.  I bought it at Home Depot.

Man, nice one. Thats it! With 4 5850's on each rig i noticed with 4 cards connected i the one in the main slot has to be clocked down a little over the others. Im using £3 cables and added my own molex power (£15+ is just a joke, by anyones standards) but no shielding. I have LOADS of aliminium tape about also. I will be doing this promptly Smiley Nice find Smiley
full member
Activity: 196
Merit: 100
September 20, 2011, 01:02:51 AM
#22
Great find, aluminum tape is so useful Smiley

Will definitely be giving this a try.
hero member
Activity: 642
Merit: 500
September 20, 2011, 12:26:18 AM
#21
I forgot to post this quite a while back, but I should have.  I'm surprised that I haven't heard this mentioned anywhere else, but I had a similar problem that took a little time to figure out.

Backstory -- When I first started putting together my first mining rigs, I noticed that some cards were performing slightly better than others.  Card performance varied anywhere from 1 to 4 percent.  It didn't make any sense.  I had 32 identical cards that had the same clock rates, so the performance should be nearly identical between cards.  At the time, I was using separate instances of Phoenix for each card instead of a combined miner, so I could see the hash rate discrepancies.

Long story short, I noticed that the cards connected directly to the board never varied...  only the cards with 1x risers did.  My rigs have 4 cards each -- 2 in the board and 2 connected with risers.  I then noticed that the hash rate in Phoenix would fluctuate when I moved the riser cable around.  Yep...  the risers easily pick up EMI from nearby components.

Since PCI Express runs at such a high frequency, it's extremely susceptible to interference over long distances.  You'll notice that most of the "name brand" risers are shielded (like this one http://www.newegg.com/Product/Product.aspx?Item=N82E16815158290).  They're shielded for a reason.

With every miner I assembled, I sat and watched Phoenix while moving the cable around until I hit the max hash rate (and then left them there).  However, I had cards that would stop mining randomly.  Sometimes they would mine for a few hours, sometimes 1/2 of a day, and sometimes days without hanging.  When they would hang, it didn't take anything more than restarting the miner.

I started logging these hangs over the course of a week or so.  I noted which machines would hang and which cards it happened to.  Of course, it always happened to the cards with the risers.

Here's what I did to fix it.  I bought a roll of aluminum duct tape and shielded the cables myself.  Be very careful with this though -- aluminum is very conductive.  If you're afraid of them touching against your components *wrap them in electrical tape* after applying the aluminum tape.  I'm sure you could use aluminum foil to shield them too, but I'd recommend the tape if you have very many risers to wrap.

After doing this, I *rarely* get a miner that hangs.  With 54 video cards mining 24/7, I only have to restart a miner about once every week or two.  It rarely happens.  Here's the exact tape that I used, but I'm sure that just about any aluminum foil will do the job.  http://www.amazon.com/Nashua-324A-Cold-Weather-Premium/dp/B0015V93KG.  I bought it at Home Depot.
full member
Activity: 196
Merit: 100
September 19, 2011, 05:32:29 PM
#20
I bought a Cablesaurus 1x-16x. They delivered quickly but it doesnt work for me at all, even with the shorting-to-recognize trick.

Since you're talking about shorting, I assume you mean you're using it in a 16x slot.

Does it work in a 1x slot?  It could simply be a bad one.
full member
Activity: 141
Merit: 100
ZOHEM | DECENTRALISED USER BEHAVIOUR DATA PROTOCOL
September 19, 2011, 04:52:00 PM
#19

 I bought a Cablesaurus 1x-16x. They delivered quickly but it doesnt work for me at all, even with the shorting-to-recognize trick.
sr. member
Activity: 322
Merit: 250
September 17, 2011, 03:26:53 PM
#18
ANyone recomending cablesauraus as either got more money than sense or works for that guy.

I use cablesaurus' adapters and I'm certainly no shill.  I really dislike paying so much for them, but he gets them out the door really quickly, it's convenient, and I've yet to hear about a bad adapter from him.

When I'm plugging my $150+ equipment into my $150+ mainboard, I'd rather have the consolation that the adapter has actually been tested.

He's also the only vendor accepting bitcoins for them unless you get them from someone random in the marketplace here.

Regardless of all that I think they should be half the price they are, but it doesn't stop me from spending a day or so of mining profit for them.

[edit] well shit, after re-reading that I guess I am a shill Wink

haha Smiley

Im in uk, so its not fast and 5 times the price Smiley
full member
Activity: 196
Merit: 100
September 16, 2011, 12:02:51 PM
#17
ANyone recomending cablesauraus as either got more money than sense or works for that guy.

I use cablesaurus' adapters and I'm certainly no shill.  I really dislike paying so much for them, but he gets them out the door really quickly, it's convenient, and I've yet to hear about a bad adapter from him.

When I'm plugging my $150+ equipment into my $150+ mainboard, I'd rather have the consolation that the adapter has actually been tested.

He's also the only vendor accepting bitcoins for them unless you get them from someone random in the marketplace here.

Regardless of all that I think they should be half the price they are, but it doesn't stop me from spending a day or so of mining profit for them.

[edit] well shit, after re-reading that I guess I am a shill Wink
sr. member
Activity: 322
Merit: 250
September 16, 2011, 11:28:01 AM
#16
I found gigabyte boards sometimes dont like 3 or 4 cards. SUprised that MSI though, i found them be solid.

I use X1 - X16 extenders, £3 off ebay. ANyone recomending cablesauraus as either got more money than sense or works for that guy. No one seems to be selling them with molex power adaptors either except him which is really frustrating. I just make them myself now from the £3 extenders. Simple
hero member
Activity: 658
Merit: 500
September 16, 2011, 10:24:20 AM
#15
It's a MSI NF750-G55.

The x16 extenders have 3 split sections and no shorts on the one I tested.


For the random BSOD/Lockups, try reinstalling your drivers! Remove the old ones first with driver sweeper or ccleaner! If you're OCing your cards, drop it back 5-10MHz and see if that helps!
I used linuxcoin and did make a new image on the flash drive to make sure, but no dice.

Since my situation differs from the OP's somewhat, maybe there's another cause?
jr. member
Activity: 37
Merit: 1
September 16, 2011, 03:37:07 AM
#14
I think motherboard makers put the locking tab on just to mess with us.
legendary
Activity: 2408
Merit: 1009
Legen -wait for it- dary
September 15, 2011, 05:34:56 PM
#13
It's just a superficial mark of the manufacturer, like the locking tab, which also shouldn't matter.

The only purpose the locking tab has ever served is frustrating the hell out of me when I want to remove just the lower card, and the damn tab is blocked Wink
2nd that!
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