OTOY Forums

asterix7 wrote:Any update on the OCTower progress or even test results - like how far have you've been able to overclock the GTX580, and what effect does it have on Octane's M/sec speed ?

Where did you find the PCIe extension cables ? My hardware shop claims it is very fragile.
Has anyone got experience with overclocking GTX590 ?

well, first off the initially choosen card seems to be cancelled; i did now switch to gigabytes gtx 580 ud (which also has some better voltage regulator circuity than the standard 580): http://geizhals.at/eu/673679. i currently own two of them and have them running stable on 900mhz. i also had a gtx 590, so i can tell you that overclocking is not it's domain; ~700mhz maybe, ~650 if you like to have it solid stable; a little more in terms of vram clocks, but a plus 5% overall performance is already the most you can get out of it.

some numbers about the gigabyte 580 (with the benchmark scene): as i waited months for the msi card to become available, i put work on the project on hold, because the plexi parts of course need to fit the card in question. i have meanwhile built some sort of test rig for the two gigabyte cards, to see if the mounting idea works in terms of temperatures, and so far it seems to be ok (still 6 more ovens are missing ;)

the extension cables i got from there:
http://www.ebay.at/itm/180694049091
http://www.ebay.at/itm/180694051125
with lenghts about 15cm they are relatively save to use; and in terms of octane rendering, there isn't persistant or heavy pcie load, so should make no problems at all...

If you are interested, I know a shop who is getting a whole set of msi lightning extreme GTX580 3Gb in stock - in Belgium. Sad to hear the GTX590 does not overclock more than 5%. Which one did you try ? I have the eVGA Classified. Will be able to try overclocking over the weekend.

What are your experiences with overclocking GTX580's then ? How far can they be pushed still to be used for rendering ?

oops sorry - ignore Q on gtx580 overclocking as you already anwered it.

asterix7 wrote:oops sorry - ignore Q on gtx580 overclocking as you already anwered it.

the problem with oc'ing the 590 is, that you can't raise voltage that high as with 580s - depending on the driver version it's max. is between .975 and 1.05 volts (without modifiying bios). another question is, how long this'd last, because the regulator circuity of all available 590 crads is lower spec. (10-12 phases) compared to that of 580s (14-21! phases); next thing are vram clocks, which help performace a lot and are limited too with 590s. and the last but not least let-down is the limited vram size. i decided to go for 580s because 1.5gb are not enough for most things i do.

regarding the msi card: i also did find some shops, which claim to have it on stock, but as soon i wanted to order them, they had sadly sold the last one only a couple of hours earlier but im happy with the gb card anyway. it takes a full 1.15v oc (even if i don't want to use it 24/7 on that level), and so the performance is quite on the level of the gb extreme...

Man this is an excellent concept..

Impressive project!
But t_3 can you tell me what model of power supply you plan to use?

Thanks

GTX580 uses around 200-240 watt, so multiply that x 8, plus add some for rest of your PC --> so I would say you prob need 2400 watt . that's 2 x 1200W supplies.
If you use GTX590 you need 240-300W peak ...

I would say the ideal winter project - will save on heating (if you have solar panels ) !

you could always go this route

DayVids wrote:you could always go this route

holy f***
what is THAT?
took me a second look to recognise that this is really an, um, gpu, um, cluster

you could always go this route

Suddenly render finished before voxelizing!