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Radeon 7950 Questions. About to Pull the Trigger.

crjackson2134 said:
Correct, to my knowledge nVidia uses soft hooks, AMD uses hardware (resistors). Flashing gets you efi but it's only 2.5 GT/s until the resistor mod.

Also, the reference card doesn't require any 6/8 pin adapters. Just plug in the 6-pin cable and the card works. It's designed to accept either, and it won't over power your 6-pin connection but you need the single fan (red) reference card as far as I know. I'm speaking specifically about the HD7970.
Click to expand...

Aaaaaah, thanks for the clarification! ;)
Well, I'm glad I chose the nVidia path then :D

About the 6 & 8 pin - same game with the beefier 680 models. They have an 8 pin connector that works perfectly fine when you just plug in the 6 pin cable.

So OP: 7950 or 7970? (or GTX680?:eek:)
 
MentalVizion said:
Aaaaaah, thanks for the clarification! ;)
Well, I'm glad I chose the nVidia path then :D

About the 6 & 8 pin - same game with the beefier 680 models. They have an 8 pin connector that works perfectly fine when you just plug in the 6 pin cable.

So OP: 7950 or 7970? (or GTX680?:eek:)
Click to expand...

Looks like I just bought 3 x 7950's. I'll sell the other two when I get them.

http://www.ebay.com/itm/Lot-of-3-AM...Domain_2&hash=item3cf65a85f1&autorefresh=true

So I'm still confused about the cables I need.

I need a 6 pin to 8 pin, and an 8 pin to 8 pin? If anyone can provide an eBay link, I'd be very appreciative.
 
sammyman said:
Looks like I just bought 3 x 7950's. I'll sell the other two when I get them.

http://www.ebay.com/itm/Lot-of-3-AM...Domain_2&hash=item3cf65a85f1&autorefresh=true

So I'm still confused about the cables I need.

I need a 6 pin to 8 pin, and an 8 pin to 8 pin? If anyone can provide an eBay link, I'd be very appreciative.
Click to expand...

You can run two six pin to six pin from the mob to the card; running it without the 8 pin shouldn't result in any serious damage. If you wanted to fully power the card you could get a dual 6 pin to 8 pin adapter for the two motherboard 6 pin connectors, and then route the rest of the power from the SATA hard drive bays to a six pin connector.
 
sammyman said:
Looks like I just bought 3 x 7950's. I'll sell the other two when I get them.

http://www.ebay.com/itm/Lot-of-3-AM...Domain_2&hash=item3cf65a85f1&autorefresh=true

So I'm still confused about the cables I need.

I need a 6 pin to 8 pin, and an 8 pin to 8 pin? If anyone can provide an eBay link, I'd be very appreciative.
Click to expand...

http://www.techpowerup.com/gpudb/307/radeon-hd-7950.html

I have no idea why this one looks different to the one you just bought.
However, it says 2x 6 pin.

So you're perfectly fine with using two 6 pin mini PCIe -> 6 pin PCIe.

You need 2 of these:
http://www.ebay.com/itm/Mini-6-pin-...011?pt=LH_DefaultDomain_0&hash=item234326497b
 
MentalVizion said:
http://www.techpowerup.com/gpudb/307/radeon-hd-7950.html

I have no idea why this one looks different to the one you just bought.
However, it says 2x 6 pin.

So you're perfectly fine with using two 6 pin mini PCIe -> 6 pin PCIe.

You need 2 of these:
http://www.ebay.com/itm/Mini-6-pin-...011?pt=LH_DefaultDomain_0&hash=item234326497b
Click to expand...

Thank you. Here is a little info on why the two cards are different:

http://www.bit-tech.net/hardware/graphics/2012/01/31/amd-radeon-hd-7950-3gb-review/2
 
sammyman said:
I have been reading a lot about this graphics card, and am close to buying one. I have a few questions before I pull the trigger.
Click to expand...

I think I may be too late in posting this as it sounds like you have already placed your order. However, I feel compelled to warn you about a Safari bug that plagues many of us Sapphire 7950 users who are running Yosemite.

It seems there was a bug introduced in Yosemite which manifests itself only in Safari (Chrome is not affected) when loading certain websites. The bug which seems to be related to a graphic driver issue (it is not present in Mavericks) causes the UI to completely freeze for 10-15 seconds at a time when loading certain website content. You can move your mouse cursor but not other UI activity happens during the freeze period. The bug seems isolated to the 7950 drivers as pulling the card out and placing any other video card into the machine eliminates the issue all together.

If you want to read more about it here are some links:

https://discussions.apple.com/thread/6863183
https://forums.macrumors.com/threads/1812731/
https://discussions.apple.com/thread/6606806 (read all three pages of the thread - the specifics are toward the end of this one)

I am affected by the bug and it makes Safari borderline unusable under Yosemite with the 7950 in the machine. From what I can tell it does not seem to be something that is being addressed in the latest public beta builds of 10.10.3 so it possibly may never be resolved.

If anyone out there is using a Sapphire 7950 under Yosemite and thinks they do not have the issue try going to www.funimation.com and browsing around a bit. If the home page loads ok try clicking on 'watch' at the top of the page. If you are able to do this without a 10-15 second freeze I will be very interested to hear about it. From what I gather the issue is unavoidable with the current Yosemite AMD drivers. Certain websites do not seem to cause any issues but others such as the one linked to above will make you pull your hair out in frustration.

At this point the only choice I seem to have is to either get rid of my 7950 or start using a different browser such as Chrome.
 
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sammyman said:
Looks like I just bought 3 x 7950's. I'll sell the other two when I get them.

http://www.ebay.com/itm/Lot-of-3-AM...Domain_2&hash=item3cf65a85f1&autorefresh=true

So I'm still confused about the cables I need.

I need a 6 pin to 8 pin, and an 8 pin to 8 pin? If anyone can provide an eBay link, I'd be very appreciative.
Click to expand...

With 7950, most were 6 pin for both plugs, only factory overclocked cards used the addition of a 8 pin plug, which yours do not appear to be. If you look at the photos in the bit-tech link you provided, you can see the 2 power connectors are both 6 pin in both photos. The 7970 cards however were 6 and 8 pins. (I have 2-7950 cards for a MacPro and a PC) So just wait until the cards arrive, chances are they will work without additional cables.

My cards are not mac-flashed, so I can swap if necessary. With a SSD as a startup, the Mac Pro has a grey screen for 8 seconds or so, then the login screen appears. Also, you cannot use the option command to select startup drives at startup (use the sys pref startup command instead and restart). Other than that, the non-flashed cards work just fine.
 
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kgapp said:
I think I may be too late in posting this as it sounds like you have already placed your order. However, I feel compelled to warn you about a Safari bug that plagues many of us Sapphire 7950 users who are running Yosemite.

It seems there was a bug introduced in Yosemite which manifests itself only in Safari (Chrome is not affected) when loading certain websites. The bug which seems to be related to a graphic driver issue (it is not present in Mavericks) causes the UI to completely freeze for 10-15 seconds at a time when loading certain website content. You can move your mouse cursor but not other UI activity happens during the freeze period. The bug seems isolated to the 7950 drivers as pulling the card out and placing any other video card into the machine eliminates the issue all together.

If you want to read more about it here are some links:

https://discussions.apple.com/thread/6863183
https://forums.macrumors.com/threads/1812731/
https://discussions.apple.com/thread/6606806 (read all three pages of the thread - the specifics are toward the end of this one)

I am affected by the bug and it makes Safari borderline unusable under Yosemite with the 7950 in the machine. From what I can tell it does not seem to be something that is being addressed in the latest public beta builds of 10.10.3 so it possibly may never be resolved.

If anyone out there is using a Sapphire 7950 under Yosemite and thinks they do not have the issue try going to www.funimation.com and browsing around a bit. If the home page loads ok try clicking on 'watch' at the top of the page. If you are able to do this without a 10-15 second freeze I will be very interested to hear about it. From what I gather the issue is unavoidable with the current Yosemite AMD drivers. Certain websites do not seem to cause any issues but others such as the one linked to above will make you pull your hair out in frustration.

At this point the only choice I seem to have is to either get rid of my 7950 or start using a different browser such as Chrome.
Click to expand...

That issue isn't isolated to the 7950 cards. I had the issue with a 5870 & 7970 cards too. It's more like an AMD driver issue.
 
crjackson2134 said:
That issue isn't isolated to the 7950 cards. I had the issue with a 5870 & 7970 cards too. It's more like an AMD driver issue.
Click to expand...

Interesting. I was unaware other cards were affected. My 5770 does not have the issue. Given that the issue may be more widespread then I previously thought I am surprised it has not received more attention.
 
kgapp said:
Interesting. I was unaware other cards were affected. My 5770 does not have the issue. Given that the issue may be more widespread then I previously thought I am surprised it has not received more attention.
Click to expand...

My understanding is that it has received attention and has improved in 10.10.3
 
since the 7970 & 7950 are based on the same GPUs as the ones in nMP, are these machines affected, too?

IMHO, Yosemite is still a mess. my PCIe RS232 card again doesn't show up in 10.10.3. it only worked in 10.10.2 and of course in 10.9.x and Mountain Lion...
 
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mikeboss said:
since the 7970 & 7950 are based on the same GPUs as the ones in nMP, are these machines affected, too?

IMHO, Yosemite is still a mess. my PCIe RS232 card again doesn't show up in 10.10.3. it only worked in 10.10.2 and of course in 10.9.x and Mountain Lion...
Click to expand...

I THINK I've heard some negative reports by some nMP users but I generally don't pay much attention to nMP threads.

I would love to go back to 10.9, but I use the new iCloud drive too much, and also continuity. If I hadn't converted my iCloud to iCloud drive I'd go back and just wait for the next version. I really hope they get all these glitches ironed out soon. I have given up on my RS-232 card and Yosemite, it's a shame.
 
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