Building a machine

[Tz2016]

So as it looks like OpenCL support is a way off I'm going to build a new machine.

I’m looking to buy three of the same cards off eBay. All these cards seem to sell for around £200. They all have similar bench marks scores. Are there any other reasons to buy one over the others?

• NVIDIA Geforce GTX 690 4GB
  GeForce GTX 780Ti 3GB
  GeForce GTX 780 6GB

For the computer I’m a little stuck. Again I’m thinking second hand to keep the costs down. I have always brought Macs and use windows under bootcamp for 3ds Max. When it come to buying a computers off eBay I feel more confident buy an old MacPro to because I know the different models. Say either a MacPro4,1 or MacPro5,1, maybe a 6-core single or 2x 4-core.

A few questions:

• Can a Mac Pro fit 3x double height cards if I loose two drives bays?
  Can I run the machine in Bootcamp for 3ds Max, and OS X for Cinema 4d?
  Will the PCI speed of the cards drop in bootcamp, does this matter for octane?
  Could I fit a GT120 with an PCI extension cable for the monitor? Would this increase performance?
  What PSU would I need for the 3x of the GPU above?
  If I were to look for a second-hand PC could anyone point me in the direction of a make or model that would be a good option, with enough PCI slots for three cards etc? HP Z800?

I really appreciate anyones advice before jumping in and buying the wrong thing.

[anklove]

Although im using only one gtx980 on 5.1 pro, no bootscreen thing and many minor bugs makes me think of buying gt120 as a system gpu. Is it worth it, do i lose performance in overall system or browsing or so?
Watching this thread.

[Tz2016]

From a bit of research I’m looking at buying a HP Z800. I think a MacPro will end up costing more and have potential issues under boot camp.

From this diagram does any know if it will be possible to fit 3x double height and 1x single gpu? I’m looking at 3x GTX 780 ti + 1x Quadro 2000

https://documentation.vizrt.com/viz-eng ... _cards_Pro

The other spec:
2x Intel Xeon X 5650 2,66 GHz 6-Core
48 GB DDR3

Would this be an appropriate PSU, the internal one won’t be enough?

https://www.scan.co.uk/products/1300w-e ... 1x140mm-fa

[Tz2016]

Any thoughts on this thread would be really appreciated. I want to get buying and building this week.