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What about the new ATI HD4850 ?


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WARNING!!! if your card is 4870 yo have to set the speed to 900MHz, the 993 value is just for 4850, maybe thats why you are getting artifacts

 

Isn't 625/993 the default anyways? with 500/750 on idle...it should be a problem only with tweaked cards.

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Isn't 625/993 the default anyways? with 500/750 on idle...it should be a problem only with tweaked cards.

 

625/993 is the default for 4850 and 750/900 is the default for 4870

 

the memory clock is different because the 4850 uses gddr3 and the 4870 uses gddr5

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I tried this wit Radeon HD 4670...The results are not great. OS X boots up, but then there is just random junk (white dots all over the place, only on black background). I checked radeon2000x.kext and 4670 device id is included

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rahil, add ur device-id to natit plist also

 

MAJITO, thx for finding the badass in drivers.

so it's powerplay.

 

If u dont want to reflash your card, here is solution, add this keys to 4800 section in natit plist

 

<key>@0,PP_DisablePPLib</key>

<integer>1</integer>

<key>@1,PP_DisablePPLib</key>

<integer>1</integer>

 

i need few success stories so i can add it to natit in pkg

 

---------

EDIT: this way was tested and it works too

also, there is another possible solution i can think of,for advanced users, if u want to have powerplay lowering chip freq, but not mem freq:

 

dump your bios, edit it with RBE as described above, then save, but dont flash it to card, instead - convert this binary file into "hex string" and add to 4800 section in natit plist as ATY,bin_image key (type - data, use Property list editor)

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Hi dear friends !!!

I found an interesting tech-info :

Palit Quitely Slips In HD 4850 Sonic Special Edition, Sports GDDR5 Memory si00067-pic.jpg

 

 

Palit has quitely slipped in a new variant to its Radeon HD 4850 series: the Palit Radeon HD 4850 Sonic Special Edition. What makes this card special, or rather different from the HD 4850 Sonic, are its memory and connectivity options. This is perhaps the first and only Radeon HD 4850 accelerator with GDDR5 memory. The card features 512 MB of GDDR5 memory across a 256-bit wide bus.

It uses an identical dual-slot cooler design to that of the HD 4850 Sonic. If the faster memory wasn't incentive enough, Palit has also expanded the connectivity options. The card provides a DVI, D-Sub (analog), HDMI and DisplayPort connectors all on the card. Owing to the Sonic branding, the card definitely sports higher clock-speeds than what AMD specifies. Further blurring the line between this card and a Radeon HD 4870, is its requirement of two 6-pin PCI-E power inputs. We are in the process of finding out its exact clock speeds, price and a larger picture.

 

Can it be that this card - because uses GDDR5(like 4870) insted of GDDR3 VRAM make less trouble ?

19a.jpg

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Can it be that this card - because uses GDDR5(like 4870) insted of GDDR3 VRAM make less trouble ?

 

That is correct but the reason seems to be that GDDR5 memory has better sync on lower frequencies. The real culprit is ATI Powerplay (ATI's power management) that lowers core/memory clocks when card is idling. Bios flashing metod just forces it to always run memory clock on full freq. but you can have some problems because he still lowers GPU (core) clock. I have managed to do it by running GioFX OpenMark minimized therefore keeping VGA out of idle state but true solution is to turn off Powerplay with two keys that netkas provided.

 

If u dont want to reflash your card, here is solution, add this keys to 4800 section in natit plist

 

<key>@0,PP_DisablePPLib</key>

<integer>1</integer>

<key>@1,PP_DisablePPLib</key>

<integer>1</integer>

 

i need few success stories so i can add it to natit in pkg

 

Netkas, one success story here.

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Netkas maybe you should create topic in the root of ATI forum with this fixed drivers and ask admins to make it sticky. This way you could post all future updates and users of HD4XXX cards would find them easily. Right now there are a lot diferent topics about HD4XXX drivers scattered across ATI board.

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So let me get this straight the shake problem is because of the card's clock going down to 500Mhz GPU click and 750Mhz Memory Clock when idling? (This is a stock saphire 4850hd bios) when under load its 625Mhz GPU click and 993MHz Memory clock. So does this mean I have to edit the bios to make all frequencies 625/993? that would suck because noise + power would increase.

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So let me get this straight the shake problem is because of the card's clock going down to 500Mhz GPU click and 750Mhz Memory Clock when idling? (This is a stock saphire 4850hd bios) when under load its 625Mhz GPU click and 993MHz Memory clock. So does this mean I have to edit the bios to make all frequencies 625/993? that would suck because noise + power would increase.

 

yes the natit modified info.plist works here but the fan noise increases and disturbs... :unsure:

sorry for my bad english :)

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if u used one of soltions for shaking, tell us which one

 

First, thx to Netkas and Majito for this very good job ;)

 

I used the third method and shaking had gone on my Asus HD4850.

All is working good. Thx one more time.

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Some new info, about leopard 10a261

aty_motmot.kext from 10.5.7 makes 10a261 to work fine with 4850.

 

just install it and natit into 261, remove (just in case) ati4800COntroller.kext atisupport.kext atiframbuffer.kext, and it works in 32-bit kernel mode just fine

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if u used one of soltions for shaking, tell us which one

 

I re-flashed my card back to it's original unedited version, and installed the Natit with BIOS package. Everything is working fine, and I no longer get any artifacts either.

 

Thanks Netkas. :)

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Have you tried SwitchResX to change resolution ?

Thanks for the feedback though now I can buy the adapter fearlessly

 

@H17737

 

I didn't. Not necessary as I already had modified the com.apple.Boot.plist file to hard code

the resolution for VESA modus as described in this thread.

Funny that only the adapter get this to work, tried a lot of combinations of attaching

monitors/TVs to DVI, VGA, HDMI, either I missed another working one or only the adapter

is really working ....

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So finally no more issued with HD 4850?? All good?

 

I want support for HD 4830.

 

Me too. I have to admit (again), that I'm a n00b in this stuff but, I can't see really how 4850 is supported and 4830 is not? I mean, they are so closely related... but well, not trying to argue with the experts :P

 

But, could the experts maybe explain why it's not supported, or more precisely, what is the problem? Netkas said something like "same as 4870 X2", but I have no idea what that means.

 

Thanks for any input :)

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