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OK.
On the picture, the R17 resistor is still présent, so if you want to get the 5.0 GT/s, you must remove it.
Are you sur the R18 resistor is now in good condition ? because on the picture you send to me it looks bad...
When you removed the R17 resistor the first time, are you sure you didn't make a tin link between the resistors ?
Your picture is not very detailled but it seems there is a tin link between R16 and R17 resistor and may be also between R18 and R17.

Really, I don't understand why it's doesn't work for you. You seem to be the only one...I'm so sorry for you.

i took this photo when i solder all back .. i also don't why its not work for me..

but doesn't matter now.. the card now gone ... brick .. go for warranty see if they will exchange another for me .. :(

maybe try again later ... :D

thank you for all you guys help ..
 
After having (successfully) done the mods myself on my PC 7950, I'd say, if you don't have installed bootcamp already, don't have a good soldering equipment and have little to no experience in soldering, it is better to buy an already modded card, have the mod be done by someone with experience or even buy the overpriced Sapphire Mac edition.

If I'd live in California, I'd probably go for a MacVidCard (despite the peekaboo he played with the 5 GT/s mod).

The problem for non US residents with US located modders is, that shipping and taxes on top of the price for a modded card brings the price close to that of a Sapphire Mac edition. Shipping in your own card for modification is also problematic as you pay shipping twice and likely have a lot of paperwork to convince custom authorities, that you don't have to pay any custom fees twice.

Thus for the 7950 it hardly makes sense and you better get a Sapphire Mac edition from a local source. It is a different story for cards, that have no official Mac version like the 7970.

If you have the equipment, the experience and a bit of spare time, you save quite some money by doing it all yourself and enjoy the sense of achievement. ;)
 
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Another thumbs up for the DIY approach - THERE IS A MUCH EASIER APPROACH - no soldering expertise required what-so-ever

As long as one look at the pictures and see where the resister is at, a small standard flat-headded screwdriver is all that's needed for this modification. All one has to do is "pop" the resister off the board: Placing the board on a flat surface, apply a small amount of pressure to the bottom edge of the resister, parallel to the surface of the board, and it will easily pop off.

Just make sure it's the correct one. :)





After having (successfully) done the mods myself on my PC 7950, I'd say, if you don't have installed bootcamp already, don't have a good soldering equipment and have little to no experience in soldering, it is better to buy an already modded card, have the mod be done by someone with experience or even buy the overpriced Sapphire Mac edition.

If I'd live in California, I'd probably go for a MacVidCard (despite the peekaboo he played with the 5 GT/s mod).

The problem for non US residents with US located modders is, that shipping and taxes on top of the price for a modded card brings the price close to that of a Sapphire Mac edition. Shipping in your own card for modification is also problematic as you pay shipping twice and likely have a lot of paperwork to convince custom authorities, that you don't have to pay any custom fees twice.

Thus for the 7950 it hardly makes sense and you better get a Sapphire Mac edition from a local source. It is a different story for cards, that have no official Mac version like the 7970.

If you have the equipment, the experience and a bit of spare time, you save quite some money by doing it all yourself and enjoy the sense of achievement. ;)
 
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Placing the board on a flat surface, apply a small amount of pressure to the bottom edge of the resister, parallel to the surface of the board, and it will easily pop off.

Interesting. Never thought about this way to "unsolder" SMD parts.

If it works, it is definitely easier than using a solder iron. Though I'm not totally convinced there is no risk of accidentally peeling off the pcb tracks in case the eyelets the resistor is soldered to are large and they've initially used a lot of solder. If that happens, you've transformed your card into an expensive door stopper. ;)
 
Interesting. Never thought about this way to "unsolder" SMD parts.

If it works, it is definitely easier than using a solder iron. Though I'm not totally convinced there is no risk of accidentally peeling off the pcb tracks in case the eyelets the resistor is soldered to are large and they've initially used a lot of solder. If that happens, you've transformed your card into an expensive door stopper. ;)

Hammer and chisel would work too :rolleyes: :p
 
Just got my 6870 to 5 GT/s without using a resistor.

(The ones I bought were too big).

NO soldering required, fully reversible.

5GTS_6870.png


I'll let you guys guess before telling you :p
 
I definitely don't have a $300 Gigabyte doorstop. :cool: The resister popped right off and on to my desk. The pesky thing is about 1/4 the size of a grain of rice and it sitting on the base of my LCD just in case it needed to go back on.


Interesting. Never thought about this way to "unsolder" SMD parts.

If it works, it is definitely easier than using a solder iron. Though I'm not totally convinced there is no risk of accidentally peeling off the pcb tracks in case the eyelets the resistor is soldered to are large and they've initially used a lot of solder. If that happens, you've transformed your card into an expensive door stopper. ;)
 
I definitely don't have a $300 Gigabyte doorstop. :cool: The resister popped right off and on to my desk. The pesky thing is about 1/4 the size of a grain of rice and it sitting on the base of my LCD just in case it needed to go back on.

Well then your resistor is in better shape than mine, who didn't survive the intimate contact with my soldering iron. ;)

I don't have plans to put a new one back, but just in case it would be nice to know the value of this thing, 10kΩ ?

Any chance you can measure the value?
 
Yikes... Sounds like flicking it off leaves it in a better state.

Well then your resistor is in better shape than mine, who didn't survive the intimate contact with my soldering iron. ;)

I don't have plans to put a new one back, but just in case it would be nice to know the value of this thing, 10kΩ ?

Any chance you can measure the value?
 
Not sure if it's related: Post modification to reference design C381, an issue has arisen where I am unable to resume from an extended sleep. (resetting the SMC has no effect)

1) Pressing the power button to wake the macPro has no effect.
2) mouse / keyboard does not wake the mac pro.
3) unplugging a USB device does not wake the mac pro
4) unplugging an active MDP -> DVI/DL adapter wakes the mac pro.
5) after wake up, the display on a non-active MDP->DVI does not display an image.

some more information about the card (unflashed) using lspci -vv

05:00.0 VGA compatible controller: ATI Technologies Inc Unknown device 679a (prog-if 00 [VGA controller])
Subsystem: Giga-byte Technology Unknown device 254c
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 256 bytes
Interrupt: pin A routed to IRQ 16
Region 0: Memory at <ignored> (64-bit, prefetchable)
Region 2: Memory at 90400000 (64-bit, non-prefetchable)
Region 4: I/O ports at 3000 [disabled]
Expansion ROM at 90440000 [disabled]
Capabilities: [48] Vendor Specific Information <?>
Capabilities: [50] Power Management version 3
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0-,D1+,D2+,D3hot+,D3cold-)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [58] Express (v2) Legacy Endpoint, MSI 00
DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s <4us, L1 unlimited
ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop+
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
LnkCap: Port #0, Speed 5GT/s, Width x16, ASPM L0s L1, Latency L0 <64ns, L1 <1us
ClockPM- Suprise- LLActRep- BwNot-

LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- Retrain- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 5GT/s, Width x16, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
Capabilities: [a0] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable+
Address: 00000000fee00000 Data: 4092
Capabilities: [100] #1002
 
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I'm french, so please excuse me for my bad english writing

This is the back of the Sapphire 7950 Mac edition :

[url=http://imageshack.us/a/img826/41/7950macedition.jpg]Image[/url]

The interesting place is the green circle.

Radeon HD 79XX PC have two type of design:

This one :

[url=http://imageshack.us/scaled/thumb/842/42248491.jpg]Image[/url]
(click on the image for larger size)

or this one :

[url=http://imageshack.us/scaled/thumb/838/68476217.jpg]Image[/url]
(click on the image for larger size)

The resistor who limit the PCI-E speed link at 2,5 GT/s, in both design, is the R17 resistor (green arrow)

To enable 5 GT/s PCI-E speed link, you must remove the R17 resistor and it's done.:)

My Radeon HD 7970 Powercolor VortexII

[url=http://imageshack.us/scaled/thumb/153/captureecran50gts.jpg]Image[/url]

[url=http://imageshack.us/scaled/thumb/6/radeon7970.jpg]Image[/url]

Thanks. I tried this on a xfx 7950 DD and it works great!
 
Running with 5.0GT/s on ATI(AMD) cards, it needs to move resistor.
On nvidia card, it needs to modify softstraps.(Where to modify softsraps)
softstraps located in 0h0058~0h0077
example for 9500GT:
The first picture is the softstraps of PC card.

If put the card in Mac OS X 10.7 or later, it will show up 2.5GT/s.

kXsqq9F.jpg


The second picture is the softstraps modified for Mac.
It shows up 5.0GT/s if you modify "1E" to "FA".

Wm6RHou.jpg


Same concept for every nvidia card but not same hex value.
If interested in the mod, please find the answer by yourself.
I just offer the hint to let you guys on the correct direction.
Don't always wait for answer from others.
By some reason, they could hide the answer for some purpose.

I just wanted to point out that this is kind of wrong. That byte has nothing to do with the speed of the bus.

Soft-straps are at 0x58, 0x5c (strap0 AND+OR), 0x60, 0x64 (strap1 AND+OR).

AND mask = select
OR mask = value

AND mask basically turns things off, while OR mask turns things on because any value ORed with 1 equals 1.

Address 0x68 (UINT16) is offset to MMIOINIT entry, while 0x6a UINT8 is a signature of the HWINFO block 0x58-0x6b, and always equals 0xa5.

Address 0x6b is a checksum of the HWINFO block computed as a sum(0x58-0x6a) % 0x100. If your checksum is incorrect, your HWINFO block will be invalid.

EDIT: Forgot to put a reference for this, Envytools, bios.c: https://github.com/pathscale/envytools/blob/master/nvbios/bios.c
 
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omni, Foul was reporting what he discovered by disassembling various Mac GT120 roms we made from an assortment of PC 9500GT BIOS.

As such, he could only report the effect, not the cause. He did not actually recognize the mechanism of how this works, hence his explanation not making sense.

Also keep in mind that how parts of PC BIOS work in Windows does not necessarily dictate their use by OSX.
 
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omni, Foul was reporting what he discovered by disassembling various Mac GT120 roms we made from an assortment of PC 9500GT BIOS.

As such, he could only report the effect, not the cause. He did not actually recognize the mechanism of how this works, hence his explanation not making sense.

Also keep in mind that how parts of PC BIOS work in Windows does not necessarily dictate their use by OSX.

Are you saying that OS X does not respect soft straps for example, or the hwinfo checksum?

That's truly mind boggling, and ass backwards (not surprising though) if Apple had chosen to circumvent the init process and pick and choose how VBIOS gets interpreted. Bah.

Care to elaborate more on this?
 
I bought XFX Radeon 7970 and first i was planning to make a crossfire setup with 2 7970. But it didn't work at bootcamp and i decided to try to make "mac edition" card from this one because it's much more quiet than my sapphire card, it have better cooling etc. So i uploaded a picture from my card and i have marked the r17 resistor there. Question is how i remove the resistor from there and is there any place where i can download new efi rom to radeon 7970 to get boot screen working? Thank you in advance from your answers.

https://www.dropbox.com/s/0ydcq642pjbr8nt/IMG_3514.JPG
 
I used a jewellers loupe (12x) and the tiniest of my watchmaking screwdrivers to just pop it off - the solder is not hard - it will give easily. You may be able to flatten or file a paperclip to make a similar tool.

When you look closely at R17 under good magnification you will see that it has a slight gap underneath it and is supported on both ends by the solder. I put the tiny screwdriver under the gap and levered R17 up from one side. I then used a bit of sticky tape to get the little solder fragments plus the resistor itself and popped it in a 5ml tube in case I needed it again.

The firmware will be on Netkas.org.

Alternatively you can end your card to MacVidCards and use his professional service and warranty.
 
I used a jewellers loupe (12x) and the tiniest of my watchmaking screwdrivers to just pop it off - the solder is not hard - it will give easily. You may be able to flatten or file a paperclip to make a similar tool.

When you look closely at R17 under good magnification you will see that it has a slight gap underneath it and is supported on both ends by the solder. I put the tiny screwdriver under the gap and levered R17 up from one side. I then used a bit of sticky tape to get the little solder fragments plus the resistor itself and popped it in a 5ml tube in case I needed it again.

The firmware will be on Netkas.org.

Alternatively you can end your card to MacVidCards and use his professional service and warranty.

I live in Finland, Scandinavia so it will be very expensive to send a card to macvidcards from here. Is there any ready ati flashing tool what makes job easier?
 
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