Boot problem with GT 120 and GTX 260 installed

[10THzMac]

I get the fans on my 285 (or on the previous 260) blowing at full tilt at start up and then they shut up after a few seconds, whatever OS I am running. I never had them running all the time. This is odd.

 

[ikold]

Your install

Pesska, can you outline how you installed your GTX 275? I just purchased a 275 and am waiding through message boards trying to figure out how to get this card to boot in OSX and Windows. Sounds like I'll need to run both video cards. I noticed that the machine has only one 6 pin power pigtail. Is that an issue that needs resolving?

Thanks

[EDIT: ok, actually read the power leads are plugged in]

Personally, I think your problem lies with the GT120. I run an 8800GT/GTX 275 setup, and unplug one card or the other depending on what I want to do, essentially disabling it so the Mac Pro can't see it at all. With your setup, both cards are powered and hence the Mac Pro can see both, and gets confused. Got access to a Mac 8800GT (flashed or otherwise) you can try? I've seen 8800GT/260 setups working fine.


So yes, its not the power problem.

 

[10THzMac]

Pesska, can you outline how you installed your GTX 275? I just purchased a 275 and am waiding through message boards trying to figure out how to get this card to boot in OSX and Windows. Sounds like I'll need to run both video cards. I noticed that the machine has only one 6 pin power pigtail. Is that an issue that needs resolving?

Thanks

It would help to know what your other card is, especially for power: 8800 needs one PCI power cable, 120 needs none. There are TWO supplied on the motherboard which need custom cables (there are post elsewhere on forums on where to get). That leaves one to find if you need three in total - most of us either power from a spare 4 pin molex in the optical bay (as I do now) or use an external PSU (as I used to).

You need to put the 120/8800 in slot one (bottom on my 08 pro) and the 275 in slot 2. I have both OS X and Windows booting from my 8800 and then use a 285 as GPU - you might not want this arrangement. For windows a clean all-nvidia driver setup will drive both cards.

Booting and drivers: under OS X there sort of separate issues of (a) starting the 275; (b) driving it properly. There is a lot of discussion about this, and for (b) we are all waiting to get our paws on the drivers that will ship with the mac edition 285. Starting a card can be done in at least three ways, depending on target hardware: EFI strings (hard), ROM Flash (might not work if you have small PC ROM chip), post boot "injection" by one of several software tools. If you are lucky enough to have access to Snow Leopard seeds with drivers you might try CoreVidia 1.1 (you might have to add the PCI ID of your card to the plist) to inject - my guess is you would probably be able to get the card up. If not, for 10.5.7 I would check back on MacForums in about three weeks, when real 10.5.7 drivers might be under discussion. We are kinda hoping Nvidia or Apple will make them widely available outside shipping with the mac card, perhaps in an update to 10.5.7.

 

[peskaa]

Pesska, can you outline how you installed your GTX 275? I just purchased a 275 and am waiding through message boards trying to figure out how to get this card to boot in OSX and Windows. Sounds like I'll need to run both video cards. I noticed that the machine has only one 6 pin power pigtail. Is that an issue that needs resolving?

Thanks

I personally don't run both cards concurrently, as driver support for OS X is a bit of a minefield at best at the moment - I'm hoping for some changes on this front when the official GTX 285 hits.

8800GT in slot 2
GTX 275 in slot 1 (lowest)

I have two PCIe power cables - one came with the 8800GT, and the other I purchased off the internet (sold as an ATi X1900 power cable). This gives me two feeds - if I'm running OS X I will simply stick one into the 8800GT and leave the other dangling loose. Running Windows I'll unplug the 8800GT's power and put both leads into the GTX 275.

The Mac is set to boot into Windows by default, as I don't get any screen display until the Vista loading screens.


Doing it this way avoids compatibility issues with OS X, and also with Vista. I'm hoping in the future that I may be able to just run the GTX 275 alone when driver/firmware solutions mature a little more. I didn't want any ugly internal power runs, and I have dual SuperDrives installed, and I certainly didn't want an external PSU.

 

[Eithanius]

I know this thread is old, but I had the same problem with my Gigabyte GTX 260 OC using netkas' injector, pair with a GT 120. It does not boot. Pair it with a 8800GT, it runs fine.

The only problem here is that the 260 uses two 6-pin power connector while the 8800GT uses one. And there's only 2 on a Mac Pro, and since mine is a 2009 MP which does not come with any 4-pin molex connector due to the SuperDrive using SATA connectors, there's no way to draw power from the PSU that way. Fortunately, the 260, being only connected with 1 connector, still runs, but the 8800GT refuse to run on CUDA, possibly due to this power-sharing problem.

Just curious, are there any foreseeable issues running the 260 card with just 1 power cable connected to it...?

Will source a SATA to 4-pin molex to fix this problem.

I've also tried plugging in GT 120 as a third card, yet still refuse to boot, so the GT 120 is definitely a culprit when paired with certain 2xx cards.

 

[10THzMac]

Just a reminder that using an external PSU is easy and mine has been running for many months now powering a 2nd PC 285 next to Mac 285. OK, it looks a total mess, but I have the flexibility to swap in a 295 or forthcoming 480. Shame about the 120 hiccups.