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I just acquired a Dell T5400 workstation for use as a virtualization platform and general purpose workstation, and I am stuck on a few things. For one, the documentation I find on it is maddeningly vague in places and sometimes contradictory, and as such I am confused as to what sort of components are compatible with it. Here is what I know:

Dell T5400 Workstation

  • 2x Xeon E5440 Quad Core CPUs at 2.83 Ghz
  • 20 GB DDR2 Fully Buffered RAM at 667 Mhz
  • 2x 500 GB SATA HDDs in RAID (I think they are mirrored, it was default)
  • OEM 875W 80+ Dell Power Supply N875E-00 (ATX)
  • Motherboard: Foxconn LS-36 (only identifying marker), socket LGA 771

At this point I would like to put a newer and better graphics card (a good enough one to last a few builds) in it than it came with (an old ATI FirePro), even though its old it has more raw power than any of my other machines. I would like to make a budget gaming rig of it, and despite the slow RAM I think it would be worthwhile. I am looking at a PCI-E 3.0 card of some kind and to that end I am trying to figure out what types of graphics cards will work with this motherboard. Some sources say 1.5 GB per card tops, others seem to imply that a 4 GB card will work just fine. The mobo has 2x PCI-Express 2.0 x16 slots, and is advertised as supporting SLI.

My main questions boil down to the following:

  • How is the maximum amount of GPU memory determined on a motherboard, and what is the real number for this unit?
  • Would it be most advisable to go with Nvidia SLI, or is Crossfire also an option?
  • I know that PCI-Express 3.0 is backwards compatible with 2.0, but how does one find the hard limit of bandwidth for a motherboard? The official user manual advertises the bus transfer rate for the PCI-Express slots as "5 GB/s/lane/direction (raw bandwidth)." What does this mean practically, and does it affect the maximum bit factor (192, 256, etc.) that a supported graphics card can use?
  • How does one go about determining the max power that this board could give to two graphics cards? It has 2 six-pin connectors for such use, and "75W" is emblazoned next to the PCI-E slots.

I know that this model Xeon is totally outclassed by newer i7s, but I would like to get the most power and use out of this model that I can. I apologize if this post is misplaced or too compressed, I am still unfamiliar with this forum and its conventions.

Thank you all for your kind help, it is much appreciated!

References from which my information comes:,d.aWc

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Answering your questions.

  1. GPU Memory is determined by the memory of your Graphics Card, system main GPU memory is determined by your primary graphics card. It's not capped by the motherboard.

  2. SLI or Crossfire is good if you want to do the investment by parts, but i personally do not recommend because SLI or Crossfire doesn't give near double performance. If you have the budget go on, but if its not the case you can buy a powerful single card and you will be ok. Using two of the best graphics cards may require you changing your power supply.

  3. Transfer rate it wont be a problem except of those cards that come with two GPU on a single board like AMD Radeon 7990 or Nvidia GTX 690, those cards may cap out the entire bandwitch of PCI Express bus connector.

  4. If your power supply only have two six-pin pci-express power connectors you may use two mid-end video cards like GTX650, or one high-end video cards that may use up-to two six pin connectors, consider that other video cards may use one six pin connector and one eight pin connector. Obviusly this depends of the video card you want to put on your system.

Depending of what use are you going to do of your system, it is depending your inversion. You may edit your question giving more details for a better answer.

share|improve this answer
My main goal was to try some virtualization, just to learn the system. The graphics card dilemma came about because I wanted to experiment with making a budget gaming system, dual booting Windows 7 and XenServer 6. Thanks for clearing up the memory issue, I had thought it might be a bandwidth limited issue. I ended up buying a Gigabyte GTX 660 OC (2 GB) and that seems to work beautifully, the only limitation is the case size (not really designed for double width cards). I think I will take your advice and only run one card, not really worth two right now. – flyingscotsman74656 Jul 22 '13 at 18:48
Aside from that I don't know what other details would be helpful for an improved answer, please let me know and I will provide what I can. Thanks for answering! – flyingscotsman74656 Jul 22 '13 at 18:48

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