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MAC PRO Graphic Card, PCIe x 4 SLI/CF Optional?

E

eXsXtReMe

macrumors newbie
Original poster
Mar 8, 2008
4
0
Hi everyone new here. I am getting my first mac and have been doing alot of research. I searched the site before asking my question. Seems that the post where old also.

Question 1.

They do offer the geforce 8800 GT now for MAC PROs the current new one that Im getting. It also says that it can hold up to 4 different graphic cards. Lets say I had 2 or 4 geforce 8800 GT graphic cards would it work SLI? If only one card was being hooked up to 1 monitor. Well than I still have the other card or cards. Gaming wise , rendering would the extra card improve my game rate and fps? I am look at the mac pro,

3.2 Quad
4GIG ram
geforce 8800 x 2. Because when you build a mac pro online it overs ATI HD 2600 x 4. So I would assume it would be more of a crossfire or SLI type thing than just being able to have 8 monitors hooked up. Correct? Combined or just for monitors? Major issue has been bothering me.

Question 2.

Also do they all have to be the same card or can one be an ATI, one a Geforce?

Question 3

Since the mac pro have pci-e 2.0 using bootcamp couldnt you just install like a ATI HD 3870 XT card and use it under windows and install the drivers or not?

Question 4

The specs for the mac pro say, 2 PCI-E x16 2.0. Than it has 2 more slots PCI-Express x 4 Interface slots. Could someone explane to me if there is a difference. Or is it just saying there are 4 PIC-E 2.0 slots. Which would make more since because they would have to be , to be able to install 4 ATI HD 2600 cards because they required PCI-e 2.0. Just the spec are hard to read on the Microcenter print outs. But when you go to order a mac pro online it gives you the option for 4 x ATI HD 2600 XT, but only gives you the option for 1 geforce 8800 GT. Maybe you would just have to call because they would not think the adverage customer would buy 2. So if I buy the geforce does that mean the other 3 slots are useless. I need someones help fast, you can see I am confused and stressed, any help would be appericated. Thank you.

I am trying to get this all on Monday for my job, and school. First time learning about a mac, Ive done alot of research and learning on my own but I need someones help on this. I would really appericate if someone would help me with this and save me a headacke so I can make a discussion. Thank you in advance.
 
eXsXtReMe said:
Question 2.

Also do they all have to be the same card or can one be an ATI, one a Geforce?
Click to expand...

I'm pretty sure if using Crossfire or SLI is possible, they'd have to be the same card, that is, you can't use SLI to connect a GeForce card to an ATI card, and likewise with crossfire. As for your other questions I'm afraid I don't have an answer for you but I'm curious about them as well.
 
You can certainly crossfire a few ATI cards, or SLI the nVidia cards, however, keep in mind that SLI and Crossfire only work in windows.

Also, you can run up to for the the ATI cards, but only 2 8800GTs as they require more power than the ATIs do.

In theory one could run dual 8800s and dual ATI cards, but it is risky to mix ATI and nVidia cards.
 
Question 1

You cannot do SLI under Windows on a Mac Pro unless you have a separate SLI connector, which doesn't work for all forms of the breed. I believe the 8800 GT is one of those that doesn't work, though I could be wrong.

As for the 4x HD2600s, no, that's just for multiple monitors, they are not in a Crossfire setup.

Question 2

You can have multiple cards, and they're more guaranteed to work if they're all nVidia or all ATI, but I have a 7300 GT and HD2600 XT in mine and they both work.

Question 3

Yes. In fact, Barefeats has installed the 3870x2 and used it to run a number of tests.

Question 4

This question's a bit unclear, so I'll do the best I can...

There are two PCIe 2.0 slots, and two PCIe 1.1 slots. The HD2600 XT doesn't really required 2.0, otherwise I wouldn't be able to use it. To get two 8800 GTs you would have to order one with the machine, and then order another one separate from the machine. No, the other slots will not be useless if you get the GeForce card, but you have to make sure you aren't drawing more power than the computer supplies.

Hope that clears a few things up.
 
1) The maximum number of 8800 GT that the Mac Pro can handle is two. They draw 220 watts of the PCI bus' maximum of 300.

Your setup is identical to the one I AM getting, but with less RAM. Actually, I think I'll be getting Nehalem, but whatever. I'm getting dual 8800 GT because I want them and because they can act as a pseudo-SLI.

The purpose of four HD 2600s is, in fact, to run eight monitors. Not do CrossFire.

2) You can mix cards. Mind you, I think the only possible mixed combinations are 1 8800 GT & 1 HD 2600 and 1 8800 GT & 2 HD 2600. I've not seen or heard of the latter one being tested, so I could very well be wrong.

3) Yes. When they come out, you could even install a 9800 GX2 and have it work under Windows. You'd need some creative power management, though.

4) Two are hardwired PCIe 2.0 16x. Two are hardwired PCIe 1.1 4x. The HD 2600 does not need 2.0 to operate. There are only two PCIe 2.0 slots in the new Mac Pro.

If you buy the GeForce, the other slots are certainly not useless. If you get one 8800 GT, you can put a wide variety of PCIe SATA, USB, FireWire, or RAID cards in the other slots. If you get two 8800 GT, you're basically limited to the Apple RAID card being put in the fourth slot.

Summary) I'm getting two 8800 GT as well. My setup will allow pseudo-SLI. There is no OS X SLI/CrossFire support. CrossFire works in Windows (with hacked drivers?). SLI does NOT work in Windows with the 8800 GT, as there are no hacked drivers for the GeForce 8 series yet.
 
Tallest Skill
You said your getting two 8800 GT as well. My setup will allow pseudo-SLI. What is pseudo-SLI and how do you set that up? Software or will I need some wire to conenct the 2 cards together. I am not sure what Power supply Watts the mac comes with first of all. Where could I find more information on pseudo-SLI. And does it work? I did a little research and it shows alot of problems and not working. Maybe you could provide me with a link where I clean learn how to make my dual Geforce 8800 GT Computers SLI. Thanks SKill.

Question 1
So bottom line question, I could get 2 Geforce 8800 and they can work together to help give me better graphics installed by themselfs =? Yes or No? or Would I have to have the pseudo-SLI setup to notice the improvement?

Question 2
If you are running a windows based graphics card in windows bootcamp, does the default mac edition card still help render graphics at all?
 
You don't need anything more than the VERY CAPABLE single 8800GT card... Unless you are a bleeding edge die for 3 more fps kinda guy... Seriously... Its a badass card... Not the absolute fastest... But thats like complaining that your Ferrari is slower than a Veyron...

My advice... Get the single 8800GT and if it isn't good enough (my money says it will be) then look at adding a different card for windows only gaming.
 
Perfect reply. You said it just for me. I am just going to buy the computer at the store and than purchase the card later, or would you think I should save 150 bucks and order it off the internet, I just dont trust the internet. Alot of people on here have 3.2Ghz but they do not sell them in stores. Only the 2.8s. Where did you buy your mac pros?
 
eXsXtReMe said:
What is pseudo-SLI...
Click to expand...

Sorry about all the confusion with semantics. It's really only me who says pseudo-SLI, as I'm the only one I've found who wants two 8800 GT...

I want two 8800 GT (actually, I might be getting Nehalem, so I want two of whatever mid-range card Apple offers. It all depends on Nehalem's release...), but I also have two monitors. With two cards, I get the full power of one card for each monitor. You can only use one monitor with SLI, but with my setup one can have the power of two cards and the space of two monitors. Granted, the card speeds remain separate for gaming, but you get the same amount of power over twice as large an area.

The GeForce 8 drivers have yet to be hacked to allow SLI on a disallowed machine. The GeForce 7 drivers have. I've read about SLI in the previous Mac Pro with the 7600. When the GeForce 8 drivers are hacked in that way, I may try SLI. I don't see why I'd need it, though.

Oh, and the Nehalem Mac Pros... Probably the same prices as the Penryns. Does anyone have any idea about what mid-range card Apple will offer with Nehalem? I believe it'll be the 9800 GT (which doesn't exist yet), and think that's a pretty fair bet.
 
Tallest Skil said:
Oh, and the Nehalem Mac Pros... Probably the same prices as the Penryns. Does anyone have any idea about what mid-range card Apple will offer with Nehalem? I believe it'll be the 9800 GT (which doesn't exist yet), and think that's a pretty fair bet.
Click to expand...

From what I was reading lately new Mac Pros "Nehalem" are not expected until 2009?! So why bother now? ;)

Also, from the past years I think we learned that Apple is not very good at implementing up-to-date graphic cards in their Mac Pros ... so in other words don't expect too much. I have more hopes that a PC 9800GT will run with modified 8800GT ROM in the Mac Pro :rolleyes:
 
Tallest Skil, If I'm to have 3 monitors solely for more real estate, would you recommend getting 2 x 8800 if I can afford it, or stick with 1x2600 and 1x8800?

Would the latter affects the graphic displays and resolution for general usage on 3x30" ACD (non-gaming)?

And if I opt for the 2x8800, is it purely just inserting the card into the PCI slot and that's it? Do I need to connect the card to anything else etc?
 
If you don't need sheer graphical power, go for the HD 2600/8800 GT combo; if it's just for light use, that setup will handle it well.

If you want another 8800 GT, you need to put it in the second slot and plug in the external power cable (the receptacle is behind the fan assembly).
 
As SLI will only work in Windows anyway (if ever) the best alternative is to get the new 9800GX2 and run it in Windows only (although I pray that someone manages to get it working in OS X :rolleyes:) ... if you have the few hundred dollars to afford the card (more than twice the price of the 8800GT :eek:)
 
orpheus1120 said:
Tallest Skil, If I'm to have 3 monitors solely for more real estate, would you recommend getting 2 x 8800 if I can afford it, or stick with 1x2600 and 1x8800?

Would the latter affects the graphic displays and resolution for general usage on 3x30" ACD (non-gaming)?

And if I opt for the 2x8800, is it purely just inserting the card into the PCI slot and that's it? Do I need to connect the card to anything else etc?
Click to expand...

Why not just use the cheaper and more than capable Radeon HD 2600 XT to power 3 monitors?
 
The new one can't, but the old one could do SLI with the 7300 and hacked drivers in Windows.

In time, the GeForce 8 series drivers will be hacked and we will be able to do SLI with the 8800 GT in Windows on the Penryn Mac Pros.
 
Mackilroy said:
Question 2You can have multiple cards, and they're more guaranteed to work if they're all nVidia or all ATI, but I have a 7300 GT and HD2600 XT in mine and they both work.
Click to expand...

I have 1900xt & 7300gt and when both cards are installed in MP, After Effects complains about Open GL when monitors are attached to 7300gt. Also FCP seems to have problems when monitors are attached to 7300gt.
Anybody else having these issues?
 
Tallest Skil said:
The new one can't, but the old one could do SLI with the 7300 and hacked drivers in Windows.

In time, the GeForce 8 series drivers will be hacked and we will be able to do SLI with the 8800 GT in Windows on the Penryn Mac Pros.
Click to expand...

Cool!

I didn't know that.... so SLI is only in software..?
Or is it that 2 PCI-e slots are both connected to the North Bridge which makes it work in theory anyway?
 
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