Luminaire Posted January 11, 2008 Share Posted January 11, 2008 Hey all. I just bought me a 20" 2.4ghz iMac with an additional gig of RAM. Just wondering one thing: XP says my card is an XT version, not a pro. The dev id (9583) is also the same as the XT version. It runs fine when gaming, no heat penalties. So having some experience with hackintosh, I figured it shouldn't get that much hotter under OSX. This tweak would be a very valuable one, and sounds like something a simple piece of software can do. 30% performance. I think I wouldn't be the only one who who just love this kind of solution. Does this exist already? Is the cause pointed out already? Is there a possible solution? If not, how can I help making such a thing? Link to comment Share on other sites More sharing options...
lessew Posted January 11, 2008 Share Posted January 11, 2008 You'd need to flash the video card firmware to a Mac 2600XT firmware I'm guessing. I don't know any Mac 2600XT cards, so you may be out of luck. The other thing with flashing it with the wrong firmware is that it's possible you'll kill the card or something... i don't know the differences between your particular model and the 2600xt, but it's probably just an increased clock (not good for iMac, as they're designed with heat in mind), and maybe some extra pipelines. Link to comment Share on other sites More sharing options...
Colonel Posted January 12, 2008 Share Posted January 12, 2008 Uhm, I would highly suggest that you don't screw around with the internals of an iMac, especially when it comes to flashing cards and intense stuff like that... Just leave it as it.. an 2600 Pro never killed anybody. Link to comment Share on other sites More sharing options...
U.C. Posted January 12, 2008 Share Posted January 12, 2008 The 2600Pro in my iMac AFAIK performs much better than an actual Pro. I can run ALL games I have tried at 1680x1050 at Medium/High settings. So I dont really see the need of overclocking. Plus this card cannot be overclocked at all. If you try in Windows, it just gives you a BSOD. I think this is due to the fact that it is a mobility version. Link to comment Share on other sites More sharing options...
skyhighmac Posted January 12, 2008 Share Posted January 12, 2008 First problem, the graphics chip is soldered onto the logic board. Unless you are able to solder with God-like abilities, you cant upgrade. Same with all of apple's laptops and the mini. So, everything except the mac pro. Link to comment Share on other sites More sharing options...
Luminaire Posted January 12, 2008 Author Share Posted January 12, 2008 Uhm, I would highly suggest that you don't screw around with the internals of an iMac I never said I was. At least not the hardware. I meant to point out that XP performs way better with games and all (like, 30%). As this is purely a software difference, I figured it shouldn't be that hard to configure the drivers in OS X to see the card as an XT. I really didn't say anything about screwing with the insides. I don't want to upgrade anything, just see if I can get the 30% extra performance XP is getting. Link to comment Share on other sites More sharing options...
skyhighmac Posted January 12, 2008 Share Posted January 12, 2008 No, that's hardware related. Link to comment Share on other sites More sharing options...
Luminaire Posted January 12, 2008 Author Share Posted January 12, 2008 Well, enlighten me. Why does XP think it's an XT, and have multiple users reported to have a ~30% performance boost (Video wise) there? Using Windows XP on your mac hardly qualifies for any hardware change. Link to comment Share on other sites More sharing options...
U.C. Posted January 12, 2008 Share Posted January 12, 2008 Do you really think hardware can just morph itself?? It s just driver/OpenGL/optimization issues. Why not try comparing WoW in Mac and Windows on the iMac? I am sure you would near same performance. Maybe the GFX is automatically under clocked in Mac, due to heating and stability issues. In fact my iMac freq used to crash in XP under heavy gaming sessions. Then I installed amcFanController in Mac, set CPU Fan to Max Speed and rebooted to Windows. Now I never have issues once I boot into Mac and then to Windows. I guess smcFanController, tells AutoFan to F*** Off and sets the speed to Max forcefully. Link to comment Share on other sites More sharing options...
Luminaire Posted January 12, 2008 Author Share Posted January 12, 2008 I am sure you would near same performance. Sadly this is not the case. I have googled some, and more users report this. It seems that it's not really a Pro, but rather an under-clocked XT. OS X seems to report the card as a Pro based on the GPU clock, as it seems to do with processors and the like. The reason for all this is that WoW and Halo 1 play MUCH faster on windows. I played WoW for 3-4 hours, and no issues came up. (fyi, I openen WoW in OpenGL mode, so it has got nothing, or very less to do with the difference between OpenGL and Direct X.) What you say sounds like OS X having some kind of GPU under-clocker (like windows has coolbits). I want to get rid of this, or at least make it tweak-able. Link to comment Share on other sites More sharing options...
U.C. Posted January 13, 2008 Share Posted January 13, 2008 Sorry cant really help you. Have you installed Tiger/Leopard with all the updates? They had a update for the new iMacs which upgraded the Graphic Drivers for better performance. Link to comment Share on other sites More sharing options...
Luminaire Posted January 13, 2008 Author Share Posted January 13, 2008 They did, now that you mention it. I still think it's not the card hardware, but rather the drivers. Couldn't I just change my dev id to that of a supposedly XT card? If I did, and it worked, I could simply tweak the fan speed up a bit if the heat is too much. Thing is, XP thinks it's an XT. So is there any way I could make OS X think that I've got an XT? I mean, I know Apple ATi cards generally have different ROMs, but I think it's very unusual that they would put the device id of "9583" on something different then what it is. AMD/ATi's site tells me this is an XT too. Some people thought that XP could think 's an XT because of the possibility of an overclocked 2600Pro... But i don't think overclocking changes Device Id's. Maybe I'll fiddle with it a bit. I'll report if I find anything. (Some context: Being in the OSX86 scene for a while, I'm kinda used to making OS X "think" something to make something work (faster). With hackintosh's it's becoming pretty regular. With PC_EFI and all.) Link to comment Share on other sites More sharing options...
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