Mac Guguen Posted January 8, 2008 Share Posted January 8, 2008 Guys, i just read that apple launched their new mac pros. Truly, that strikes me, specially with the option of display cards, however, i was wondering if, just maybe that we are able to Play with either SLI/ Crossfire, i mean they wouldnt let us use geForce 8800 GT and not knowing that we will play with SLI right? and is it possible to Put a GeForce 8800GTX instead of a GT, and play SLI with 2 of GeForce 8800GTX?? Link to comment Share on other sites More sharing options...
Soündless Posted January 9, 2008 Share Posted January 9, 2008 i dont think that os x supports crossfire/sli Link to comment Share on other sites More sharing options...
apowerr Posted January 9, 2008 Share Posted January 9, 2008 I don't think the motherboard supports SLI/Crossfire. I'm pretty sure they're using some other method to get multiple video cards working. Correct me if I'm wrong. Also, like Soundless has said: OS X does not have SLI or Crossfire support. Link to comment Share on other sites More sharing options...
Synaesthesia Posted January 9, 2008 Share Posted January 9, 2008 and is it possible to Put a GeForce 8800GTX instead of a GT, and play SLI with 2 of GeForce 8800GTX?? Unfortunately you can only use "apple brand" graphics cards in an Apple computer. Link to comment Share on other sites More sharing options...
Mac Guguen Posted January 9, 2008 Author Share Posted January 9, 2008 well, i dont see why i cant play with SLI/Crossfire i mean, now that the motherboard can support 2x X8 PCI-E, i just dont see why? And with GeForce 8800GT available for us, i believe 8800GTX will be able to fit in with a bit of hacks, since the power input needed aint much comparing ot 8800GT, correct me if im Wrong. Yes i also know that Apple needs Display Cards made by itself but what happens if hackers on web was able to put 2 8800GTX and SLIed it? i mean its not impossible is it? And yes i know OS X cannot support SLI, but can i have SLI for Windows Vista?? Meaning i keep them connected on SLI together, but Mac only runs 1 of the 8800GTX and when i boot in Windows Vista, it runs both? Is that possible? Link to comment Share on other sites More sharing options...
apowerr Posted January 9, 2008 Share Posted January 9, 2008 Something to note: The 8800GTX isn't that much better than the 8800GT. Also, I've looked it up and SLI/Crossfire is just not possible from what I can tell. Whenever you're doing SLI or Crossfire, you use a special motherboard with special chipsets. Link to comment Share on other sites More sharing options...
Azurael Posted January 9, 2008 Share Posted January 9, 2008 Both CF and SLI would work fine on the Mac Pro with hacked drivers under Windows. Any chipset limitations you've heard about are merely artificial limitations in the drivers from ATI and NVidia. I believe that CF should work without hacked drivers, in the future, if now now, since ATI has always supported CF on pretty much all Intel chipsets. The only real requirement for SLi/CF to work is a chipset with inter-channel communication on the PCIe bus, and I don't know of any that don't support that. What performance would be like with one card in x4 mode, I don't know, though it may not make as much difference as you'd expect. Neither CF nor SLi work in OS X though. Link to comment Share on other sites More sharing options...
Paranoid Marvin Posted January 9, 2008 Share Posted January 9, 2008 I want a Mac Mini with dual 8800 Ultras Link to comment Share on other sites More sharing options...
Alessandro17 Posted January 9, 2008 Share Posted January 9, 2008 I want a Mac Mini with dual 8800 Ultras Sure! And I want to find a one million Euro cheque in my letterbox tomorrow Link to comment Share on other sites More sharing options...
Cohen The Barbarian Posted January 11, 2008 Share Posted January 11, 2008 The Mac Pro uses a server-style motherboard running the Intel 5000 series chipset. Dual-socket 771 supporting the LGA 771 Xeon processors. Using SLI requires a nVidia chipset. Crossfire can be implemented on Intel chipsets but requires some tweaks to the mobo that the Mac Pro does not have. You also cannot use a generic PCIe video card in the Mac Pro because it uses EFI, so the flash ROM on the video card must be programmed for EFI. PC video cards like you get anywhere are all for use in a BIOS environment. This is similar to the older PowerPC based Macs...they used Open Firmware as the BIOS and only cards programmed for OF would work. That was why you couldn't grab any AGP video card and plug it in. I haven't looked at the cards inside the Mac Pro, but even if they have an SLI connector neither the Flash ROM or the EFI system are programmed to activate it. The motherboard still has to supply the data to the cards' via the PCIe bus and without the BIOS/EFI set to direct the traffic correctly it wouldn't work right. This is why you have to turn SLI "on" in a normal PC BIOS. It changes the way the video cards register themselves to the driver. Link to comment Share on other sites More sharing options...
asap18 Posted January 11, 2008 Share Posted January 11, 2008 lol @ Alessandro's sig /me runs away like a little girl Link to comment Share on other sites More sharing options...
Azurael Posted January 15, 2008 Share Posted January 15, 2008 I haven't looked at the cards inside the Mac Pro, but even if they have an SLI connector neither the Flash ROM or the EFI system are programmed to activate it. The motherboard still has to supply the data to the cards' via the PCIe bus and without the BIOS/EFI set to direct the traffic correctly it wouldn't work right. This is why you have to turn SLI "on" in a normal PC BIOS. It changes the way the video cards register themselves to the driver. That's simply not true... With the 'hacked' drivers, which can be found at places like Guru3D, you don't need to set anything special in the BIOS, otherwise it wouldn't work on chipsets which weren't designed to be SLI capable and have no such BIOS options to start with. As I said, at a base level, the only requirements for either SLi or CF is a chipset which allows intercommunication on the PCIe bus (which is all chipsets.) Of course you have to 'enable' SLi on most genuine SLi boards, because otherwise you'd have to lose half the PCIe lanes to the second slot when you're not using it (incidentally, there is an ECS 650i which does have it's slots wired like this - permanent x8/x8!) - of course that's not the case on 680/780 but any options in the BIOS are merely optimisations, which in the case of my FP-IN9 actually made SLi (the pointless beast it was) slower when enabled! Now, whether SLi or CF would be worthwhile with one card in x4 mode is another question altogether, but there's definitely no reason for why it wouldn't work in Windows. You don't even need an EFI ROM on the card for it to work in Windows on a Mac (it gets initialised via the regular video BIOS by the CSM), so what you think EFI's got to do with it, I don't know. Link to comment Share on other sites More sharing options...
Cohen The Barbarian Posted January 15, 2008 Share Posted January 15, 2008 That's simply not true... With the 'hacked' drivers, which can be found at places like Guru3D, you don't need to set anything special in the BIOS, otherwise it wouldn't work on chipsets which weren't designed to be SLI capable and have no such BIOS options to start with. As I said, at a base level, the only requirements for either SLi or CF is a chipset which allows intercommunication on the PCIe bus (which is all chipsets.) Of course you have to 'enable' SLi on most genuine SLi boards, because otherwise you'd have to lose half the PCIe lanes to the second slot when you're not using it (incidentally, there is an ECS 650i which does have it's slots wired like this - permanent x8/x8!) - of course that's not the case on 680/780 but any options in the BIOS are merely optimisations, which in the case of my FP-IN9 actually made SLi (the pointless beast it was) slower when enabled! Now, whether SLi or CF would be worthwhile with one card in x4 mode is another question altogether, but there's definitely no reason for why it wouldn't work in Windows. You don't even need an EFI ROM on the card for it to work in Windows on a Mac (it gets initialised via the regular video BIOS by the CSM), so what you think EFI's got to do with it, I don't know. OK...so using an older, hacked driver you can get close to native SLI performance on some chipsets. I say this because the forum topics I read on the hacked driver shows mixed results. A BIOS/chipset tweaked by the GPU manufacturer for the SLI system will still perform better, but I'm not a fan of nVidia's chipsets. (Now...seeing this, don't think I won't screw around with it on one of my systems running XP just for kicks.) Now...this thread is about SLI in a Mac Pro. Not a Hackintosh using BIOS, but a real Mac. Macs use EFI...video card must communicate with the EFI on bootup or it does not work. So if the Mac video card does not have a SLI connector then you are out of luck before you even get started. If it does, then you have to determine if a generic BIOS-based PCIe video card in a second slot will function without registration to the EFI system. Remember, EFI performs the functions that BIOS does, which is setting up the IRQ/timing/DMA. Many people have tried putting regular PC video cards in the Mac as a second monitor (not even attempting SLI) and they simply do not work. They have to be EFI cards. Even if the Mac video card has SLI, I doubt that it would function as a "bridge" for a second card to actually work. And then you get to start addressing drivers in OS X... The OS does not matter at this level...so booting Windows with hacked drivers isn't even part of the equation. If the EFI does not register the card correctly then the OS does not have a clue what is sitting in the slot. Mac users have wished for years that they could use cheaper, generic PC video cards. Macs have used AGP and PCI/PCIx/PCIe for years now, but video cards had to support Open Firmware and now EFI or they just will not work. Apple will not begin to implement SLI on an Intel 5000 chipset because that would {censored} off nVidia. nVidia wants you to buy their chipset for SLI, but no nVidia chipset supports dual processor Xeons. nVidia is a big supplier to Apple, so they wouldn't risk it. Without Apple supporting it, it probably won't happen. Anyway, I stand corrected on the SLI on non-SLI chipsets...I remember the days of having to move jumpers to allow SLI on older nForce chipsets. Interesting to see driver hacks allowing it now. Work doesn't allow me the time to dig into hardware/sfotware engineering like I used to, so I'm getting a touch behind. As far as the Mac system go, I am up to date on it since work has pushed me to get my Apple Certified Technician status for both Desktops and Laptops. Thanks for the info on Guru3D....it gives me something else to tinker with. Link to comment Share on other sites More sharing options...
cmdshft Posted January 15, 2008 Share Posted January 15, 2008 Well, why doesn't someone see if they can't find out how Apple get's the MacPro's to run up to 4 graphics cards? That could solve a lot of the mystery... I might just go to the Apple store tonight and ask a Mac Specialist and watch their jaws drop. Link to comment Share on other sites More sharing options...
Azurael Posted January 15, 2008 Share Posted January 15, 2008 The question of running 4 GPUs is irrelevant. Any system with multiple X16 physical slots can run as many graphics cards as it's got slots. SLi/CF isn't just about using multiple graphics cards. It's about allowing the output of a single application to be spread across several cards. Now...this thread is about SLI in a Mac Pro. Not a Hackintosh using BIOS, but a real Mac. Macs use EFI...video card must communicate with the EFI on bootup or it does not work. So if the Mac video card does not have a SLI connector then you are out of luck before you even get started. If it does, then you have to determine if a generic BIOS-based PCIe video card in a second slot will function without registration to the EFI system. Remember, EFI performs the functions that BIOS does, which is setting up the IRQ/timing/DMA. Many people have tried putting regular PC video cards in the Mac as a second monitor (not even attempting SLI) and they simply do not work. They have to be EFI cards. Even if the Mac video card has SLI, I doubt that it would function as a "bridge" for a second card to actually work. And then you get to start addressing drivers in OS X...I'm not talking about OS X for one moment. It's out of the equation because it simply doesn't support SLi/CF as far as I know. One thing you are missing is that the CSM on an Intel Mac fully initialises the graphics card, as the BIOS would in a real PC. You can use any number (including running without a single EFI card) of standard, off the shelf PC graphics cards in a Mac Pro, but they will only be initialised either after somehting like NVinject has run in Mac OS, or under any OS which boots using the CSM (i.e. Windows, Linux, Whatever.) because the CSM initialises the graphics card in exactly the same way as a real BIOS does.I would say with almost a hundred percent certainty that SLi or CF would work fine on a Pro with the right hacked drivers. I'd even be willing to try it if I had more than one identical graphics card. What you'd be sacrificing in terms of performance and OS X compatibility, I can't say. I can't see any reason though, since Apple's EFI cards have both an EFI firmware and a BIOS firmware built in (purely for this CSM capability) that even if you had multiple Apple 8800GTs, for example, that the hacked drives wouldn't also work on those if you hook up an SLi bridge between them (although I don't know that the SLi connector is present on Apple cards.) Link to comment Share on other sites More sharing options...
nagal Posted January 15, 2008 Share Posted January 15, 2008 You can use any number (including running without a single EFI card) of standard, off the shelf PC graphics cards in a Mac Pro I can say with first hand knowledge, trying to use a PC NVidia 7300GT in a MacPro with NVinject installed, the MacPro would not boot. Link to comment Share on other sites More sharing options...
Azurael Posted January 16, 2008 Share Posted January 16, 2008 I've booted a Mac Pro with an 8600GT and a 7800GTX into Windows fine, and the 7800GTX into Mac OS fine with Natit (I did this before the 8600 was supported in OS X) Link to comment Share on other sites More sharing options...
nagal Posted January 16, 2008 Share Posted January 16, 2008 I've booted a Mac Pro with an 8600GT and a 7800GTX into Windows fine, and the 7800GTX into Mac OS fine with Natit (I did this before the 8600 was supported in OS X) Wow first time I ever heard of anyone having success doing that. Not doubting you but it is interesting as I would love a card a bit beefier than my 7300GT. Was the screen black until Natit kicked in? Link to comment Share on other sites More sharing options...
vbetts Posted January 16, 2008 Share Posted January 16, 2008 From what I read, the 8800GT in the MacPro cannot do SLI, or if it can the MacPro doesn't have this feature for it. However, the HD2600 has the ability to do quad crossfire in the MacPro. Link to comment Share on other sites More sharing options...
Mac Guguen Posted January 16, 2008 Author Share Posted January 16, 2008 Vbetts, i thought we cannot do either CF/SLi by what was told, so basically its not Quad CF on 4 HD2600, it basically gives you the option to show 2 Monitors/card with the performance of only 1... I dont understand why Apple is so stupid enought to ignore that SLI/CF is taking the market and not doing anything about it. I mean even they give us 4 PCI-E bars with 1 pre built display card, than why have that many when you cant even bind 2 display cards into 1?? Also WTS HAPPENING TO APPLE STOCK??? i bought them at 180$ a week ago and now its 159$ WTF is happening?? Link to comment Share on other sites More sharing options...
Wrenbird Posted January 16, 2008 Share Posted January 16, 2008 I want a Mac Mini with dual 8800 Ultras :censored2: but imagine the heat issues... Link to comment Share on other sites More sharing options...
vbetts Posted January 17, 2008 Share Posted January 17, 2008 Really I do not see the point in 4 2600s if there is no real performance benefit. Which is kind of sad to see, since the HD2600s aren't the greatest cards, but 4 of them would get the job done. What they're basically doing is wasting more power than needed, there has to be some reason with the x4 HD2600 option. The 7300GT had this option too, gonna be dissapointed if there's no real gain for it. One thing though that the Mac Pro has that most PCs don't even have yet, is PCIE 2.0. Although it's not like there's any current video card that will have a huge performance difference from PCIE to PCIE 2.0. EDIT-Something else though you have to remember. The Intel P35 does have the ability to do "crossfire" but it's not crossfire with ATI cards that have the dual link, and not the master and slave cards. Could it be that Apple has a different method of syncing the cards together? Link to comment Share on other sites More sharing options...
Mac Guguen Posted January 17, 2008 Author Share Posted January 17, 2008 Hmm, vbetts, i totally agree with you about the Intel P35 having Crossfire but not crossfire with ATI Cards... Yes there maybe a way to do this, Apple received numerous complaint on its previous Mac Pro not Having enough power to SLI/Crossfire Now that they put the ability to have 2x 16x with 1 running 8x if 2 displays are inserted. I guess they are now taking all the complaint to actions, but dont understand why they give High-End display cards for sell when Mac doesnt support SLI/CF. Unless they want to tell me that 4 Display cards is just to show 8 Monitors... and i will be like WTF, who NEEDS 8 monitors?? JUST GIVE US SLI/CF and we'll dam get your product!! STEVE, you moron, Mac world sucked introducing MacBook Air, Who even needs it?? i mean it doesnt read CD, it only have 80GB and CPU is so {censored} that not even Microsoft Outlook can be started together with Keynotes!!! STEVE give US SLI/CF and we'll love you. 1 things for sure, IF apple succeed to make a computer with a server based Mother Board to run 2 LGA 771/775 CPU with SLI/CF function, You will be a super hero in the computer industry, cause theres no Motherboards that can best fits 2 CPU and run SLI by then!!! Link to comment Share on other sites More sharing options...
vbetts Posted January 17, 2008 Share Posted January 17, 2008 The cpu in the Air is the same model in the MacMini. Besides that it's ultra low voltage. Link to comment Share on other sites More sharing options...
Mac Guguen Posted January 27, 2008 Author Share Posted January 27, 2008 well, not that i want to say this but apply doesnt have the advance in GPUs i can tell you that. If they are strong they can program the intel chipsets on the Mac Pro to be able to read 2 display cards or more together giving this chipset to be able to both Play with SLI and CF, then trust me, everyone will be swarming for Mac Pro instead of a HP Blackbird/Alienware {censored} Link to comment Share on other sites More sharing options...
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