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dany123

macrumors newbie
Original poster
Dec 20, 2013
7
0
Hi there!

My dad just bought me a MacPro 3,1 with 2x Quad Core Cpus (2.8GHz). This is the early 2008 model.

I currently have a desktop with the following specs:

i7 930 (2.8ghz quad core)
6gb RAM
Sapphire R9 280x Vapor-X Edition

Now here's the thing. I want to swap my 280x into the MacPro but of course, Apple only has 6 pin connectors and my card requires two 8 pin connections. I read a lot about this topic in this forum, and it seems as though it is very risky to use a 6pin to 8pin converter. My card is on the high side of power draw (I heard it can reach 460W but I don't think that is accurate... it's rated at 250W TDP). I really don't want to modify the case in anyway. Should I just keep my current desktop or is there a way to throw in my card into the mac? I'd much rather have two quad core processors than one. Also, I do not want to spend too much money. I've already burnt about $600 upgrading my previous desktop (I had to buy a 1000w PSU because I was planning on getting a second 280x).

Thanks for your help!
 
Hi there!

My dad just bought me a MacPro 3,1 with 2x Quad Core Cpus (2.8GHz). This is the early 2008 model.

I currently have a desktop with the following specs:

i7 930 (2.8ghz quad core)
6gb RAM
Sapphire R9 280x Vapor-X Edition

Now here's the thing. I want to swap my 280x into the MacPro but of course, Apple only has 6 pin connectors and my card requires two 8 pin connections. I read a lot about this topic in this forum, and it seems as though it is very risky to use a 6pin to 8pin converter. My card is on the high side of power draw (I heard it can reach 460W but I don't think that is accurate... it's rated at 250W TDP). I really don't want to modify the case in anyway. Should I just keep my current desktop or is there a way to throw in my card into the mac? I'd much rather have two quad core processors than one. Also, I do not want to spend too much money. I've already burnt about $600 upgrading my previous desktop (I had to buy a 1000w PSU because I was planning on getting a second 280x).

Thanks for your help!

The max TDP figures you read are likely for the entire system, not just the GPU. That said, while I generally believe it's okay to go ahead and just use the adapters, know that doing so is at your own risk. To my knowledge, the 280X is just a rebadged 7970 GHz, which many people use without issue.

Do you need the dual quad-core processors? If you do not use those extra four threads, I believe the E5462s in your Mac Pro are actually slower than the i7-930 you already have.

Do you know how much you dad spent on the 3,1? Also, get more RAM. That is by far the cheapest upgrade, and 6GB is kind of low.
 
The max TDP figures you read are likely for the entire system, not just the GPU. That said, while I generally believe it's okay to go ahead and just use the adapters, know that doing so is at your own risk. To my knowledge, the 280X is just a rebadged 7970 GHz, which many people use without issue.

Do you need the dual quad-core processors? If you do not use those extra four threads, I believe the E5462s in your Mac Pro are actually slower than the i7-930 you already have.

Do you know how much you dad spent on the 3,1? Also, get more RAM. That is by far the cheapest upgrade, and 6GB is kind of low.

My dad spent $350 on it. It has 10GB of RAM. (4+4+1+1)

My graphic card came with molex -> 8 pin converters. Are there any molex points I can squeeze power out of in this mac pro?

Edit: I also don't mind if my computer is slightly slower. I just fell in love with the build quality of this mac pro from the second I saw it. It came with a 8800 GT which is too weak for gaming in my opinion. Do you think an 8800 GT can handle a game like League of Legends at 1220p/1440p?
 
My dad spent $350 on it. It has 10GB of RAM. (4+4+1+1)

My graphic card came with molex -> 8 pin converters. Are there any molex points I can squeeze power out of in this mac pro?

That's a pretty good price. Not easily, the power supply is not easily accessible. I don't know if this is an option, but you could consider flipping it for a few hundred in profit.

What exactly did you upgrade on your last computer that cost $600?
 
That's a pretty good price. Not easily, the power supply is not easily accessible. I don't know if this is an option, but you could consider flipping it for a few hundred in profit.

What exactly did you upgrade on your last computer that cost $600?

He told me the same thing. He said he can sell it and get $650 easily. In terms of my computer, I upgraded the GPU to the 280x vapor-x edition which cost me $400 with taxes, alongside a 1000W power supply for $170 and an SSD for $100. So actually... I spent closer to 700 lol. I just really like the build quality of the macpro and I want to switch to it. I can give this desktop to my bro and throw in the GTX 460 I have lying around.

I really do not want to burn out the macpro with those adapters. The ports are specified to 150W and my card TDP is 250W.
 
He told me the same thing. He said he can sell it and get $650 easily. In terms of my computer, I upgraded the GPU to the 280x vapor-x edition which cost me $400 with taxes, alongside a 1000W power supply for $170 and an SSD for $100. So actually... I spent closer to 700 lol. I just really like the build quality of the macpro and I want to switch to it. I can give this desktop to my bro and throw in the GTX 460 I have lying around.

I really do not want to burn out the macpro with those adapters. The ports are specified to 150W and my card TDP is 250W.

I was asking about your upgrades to see if they were sunk into the old PC, which fortunately, they are not aside from the PSU. Again, I had to ask if you needed the extra threads, because if not, in terms of day-to-day tasks, it'll actually be slower.

Here are two alternatives if you want to use OS X. First, you build yourself a Hackintosh and repurpose most of the parts you already have. I know first gen i7s still have a lot of resale value, and you can honestly probably upgrade to a Haswell for minimal cost after resale, maybe a net of ~$100. I just purchased a B85 Haswell board for my brother with a Haswell Xeon for around $300. It'll be much easier to Hackintosh than your i7-930. If you chose to flip the '08, you could easily fund the upgrade.

Alternatively, you could try to scoop a 2009 model. These are superior because they can easily be flashed to be identical to the 2010/2012 models, and CPU upgrades are a steal. This will not be cheap overall compared to the first option though. Think ~$1000-1200 for the MP and around $100 for 24GB of RAM. Do note that you can get 2x6-core X5650s for this computer for around $350 on eBay.
 
I was asking about your upgrades to see if they were sunk into the old PC, which fortunately, they are not aside from the PSU. Again, I had to ask if you needed the extra threads, because if not, in terms of day-to-day tasks, it'll actually be slower.

Here are two alternatives if you want to use OS X. First, you build yourself a Hackintosh and repurpose most of the parts you already have. I know first gen i7s still have a lot of resale value, and you can honestly probably upgrade to a Haswell for minimal cost after resale, maybe a net of ~$100. I just purchased a B85 Haswell board for my brother with a Haswell Xeon for around $300. It'll be much easier to Hackintosh than your i7-930. If you chose to flip the '08, you could easily fund the upgrade.

Alternatively, you could try to scoop a 2009 model. These are superior because they can easily be flashed to be identical to the 2010/2012 models, and CPU upgrades are a steal. This will not be cheap overall compared to the first option though. Think ~$1000-1200 for the MP and around $100 for 24GB of RAM. Do note that you can get 2x6-core X5650s for this computer for around $350 on eBay.

Thanks a lot for your help so far bro. I don't want to do the second option because it'll take me quite some time to pick one of those up for cheap and it's such a hassle. I don't want to sell my current setup or my macpro, sorry if I sound stubborn. I want the assurance that I can always go back to this desktop and the only way to do that is to let my brother use it. If I ever need to swap after that point I can just give him the macpro.

Another reason I want the macpro is the convenient HDD slots. I have 3HDD's (1.5TB~2TB each) in my NAS that I can take out and put into the mac, converting it to my NAS. I also program quite frequently on both linux and windows (C#), so I like having a unix shell for all of my non-C# work.

My current setup is actually amazing for hackintoshing. I've done it before and it worked flawlessly (the UD3R rev 2 is an amazing mobo for this stuff). The Mac Pro though.. I'm a system builder and I've never encountered something so clean. I don't want to waste time trying to decipher all of it though, so I'm here asking about my options in terms of powering my GPU. Is there any Molex output from the PSU that I can couple with the 6+6pins to get ~ 275W (225W threshold + 50W from molex) for my GPU? I found some 6pin to 8pin converters for ~$17 at a local store, and I only want to buy one. If I can use these two molex converters (molex to 8pin) I have though that would be amazing.
 
He told me the same thing. He said he can sell it and get $650 easily. In terms of my computer, I upgraded the GPU to the 280x vapor-x edition which cost me $400 with taxes, alongside a 1000W power supply for $170 and an SSD for $100. So actually... I spent closer to 700 lol. I just really like the build quality of the macpro and I want to switch to it. I can give this desktop to my bro and throw in the GTX 460 I have lying around.

I really do not want to burn out the macpro with those adapters. The ports are specified to 150W and my card TDP is 250W.
There is one molex in dvd drive bay. It's not easy But you can get the wires to vga, then molex->6-pin , 2 6-pin-> 8-pin. This molex wont provide much energy, maybe just 20-25 additional watts, but should be enough.
 
There is one molex in dvd drive bay. It's not easy But you can get the wires to vga, then molex->6-pin , 2 6-pin-> 8-pin. This molex wont provide much energy, maybe just 20-25 additional watts, but should be enough.

So basically one 8pin will provide 150W+ and the other 8pin will only add 25W? Does it matter that there's so little power going into the second 8pin slot?

Also, I might go buy two of these http://www.canadacomputers.com/product_info.php?cPath=90&item_id=041818 tmrw if you guys think that it will boot and work with the r9 280x vapor-x edition. Remember the vapor-x is overclocked (pretty close to the cards limit).
 
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bumping, the store closes in 2 hours I need help asap.

Edit: An update:

I went ahead and bought two of the 6pin -> 8pin adapters. The problem is... my macpro only has one of those 6pin -> 6 pin cables and I don't have the box. Does anyone know what this wire is called? It connects to the motherboard and puts out the standard 6 pin plug.
 
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Hey guys.

I ended up using an external PSU (430W) to power my graphics card. It is running beautifully under osx. Now I have another issue (lol):

I'm trying to install Windows but of course i can't see anything when my computer boots up because my graphic card is still running a bios firmware. How can I flash my r9 280x to have EFI? Thanks.
 
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