Evening all! Anyone know if you can chain PCI-e riser cables for a GPU without impact on performance? It's for a GTX460 and I have two 15cm risers (can't find anything longer in single form). Thanks in advance!
Thanks Kayin - where do you get this from, though? I could hardly find anything online about the subject.
Experience, mostly-but you're running a LOT of bandwidth through unshielded, untwisted pairs. Crosstalk should happen almost immediately. It's one reason we recommend that you don't use a riser unless 100% necessary. Even KR only has a right angle adapter, and it's all PCB-there's no ribbon cable at all. I'm planning to upgrade the graphics before buttoning it up, so I went with a right angle only. Lots of cards won't tolerate them that long because they pass more info (or simply larger sizes) and I'm taking that into account. You could try wrapping them with lead foil, but I think you need shielded cables to begin with. https://bitcointalk.org/index.php?topic=38331.20 Bitcoin miners probably know the most about them. My setup is geared more towards Tesla level operation, so only one card.
Ive got about 6 of these running with no issues for mining I dont know what there like when gaming etc sent from me phone
True, but did you stick them end-to-end? That's the OP's question. However, yes, you probably know a fair bit more about them than me. Like I said, KR's setup is actually just to lay the card flat on the board.
Cheers guys - appreciate the input. I've gone with using a single riser for now and pulling some hair out trying to make everything fit. It's for a project I'm working on that I hope to be able to post a log for very soon, but the deadline has been brought forward so I'm flat out trying to get it completed at the moment, often till quite late at night. Design issues! Anyway, I know the system worked when the card was plugged straight in so I'll check it again with the single riser once it's built. Any issues and I'll shield it using the alu foil and see if that helps. I can't use a right-angled PCB-only riser as the case won't allow it. Kayin - that link was pretty good reading so thanks for sending it on (+rep). What's KR though?
Ah! Nice one. Off-topic, I know, but I checked it out and can only see pics on the last page - do I need to change a setting? Hoping this might inspire me to get mine up (complete with annoying riser cable. Back on topic!).
Hey guys, been a while but I've more info/questions that relate now that the project is back on the rails following another deadline change. It seems the GTX 460 I'm using for my build works with a single 15cm riser but not the powered 30cm one I've got. Might not be a huge issue as I think I've managed to fit everything into the space I have available, but if I can use the 30cm one it might give me some more flexibility in terms of positioning. However, hooking up the 30cm cable means I can POST, see the Windows splash screen but then nothing from the video output. Also, this only happens using the VGA connector - the two digital ones refuse to send any signal at all. The riser is powered, via molex, so I had high hopes for this working - does anyone know if the card just needs more power, or if this is going to be impossible due to the length of the ribbon? And is that no-digital issue something anyone has see before? It might just be that I have no chance with the longer cable, as suggested above a while ago
Ah, cheers Rollo. So if I interpret correctly, the 30cm riser (even though powered) doesn't get enough data up to the GPU to display the desktop, but for mining, this data requirement is much lower. So do these long 16x slot cards exist solely to make use of spare 16x slots ie. they don't push anywhere near enough data through? You'd then still need either onboard graphics or a GPU directly in a slot on your mining rig, true?
The powered ones are only for cards that draw a lot of power through the socket, things like the GTX 480 or 5970 for example. They do not provide you with a better signal, they just make sure the ribbon doesn't melt.
