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if you now dump your System ROM and open it up in the microcode tool, can you see the new Penryn Microcode still?

alternatively can you Boot an older OS (something 10.7.5 or older)

and run the same sysctl command? the older OSs cant/dont load Microcode after booting so running the sysctl command and looking at the microcode value will tell us the BootROMs one.

I noticed in some cases Colins Flasher Tool will still report a success even if it failed to Flash the BootROM.

I dumped the rom when I tried my self earlier using a Penryn Microcode I found and it flashed successfully.... I can boot any OS from Snow Leopard Up, I will go with Lion and get back to you :)
 
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I dumped the rom when I tried my self earlier using a Penryn Microcode I found and it flashed successfully.... I can boot any OS from Snow Leopard Up, I will go with Lion and get back to you :)


if your feeling really adventures you could try flashing an iMac8,1 BootROM to your iMac7,1 and see if that works :D

I have a good feeling it should work given how similar the 2 machines are but it does carry a higher risk of bricking the machine.
 
if your feeling really adventures you could try flashing an iMac8,1 BootROM to your iMac7,1 and see if that works :D

I have a good feeling it should work given how similar the 2 machines are but it does carry a higher risk of bricking the machine.

considering a logic board is £15 :p I am prepared to give it a go if you have a 8,1 20" Stock rom?

OSX Lion (System still reports it is a 400Mhz Proc :(

Bens-iMac:~ beneyre$ sysctl -a | grep machdep.cpu
machdep.cpu.max_basic: 10
machdep.cpu.max_ext: 2147483656
machdep.cpu.vendor: GenuineIntel
machdep.cpu.brand_string: Intel(R) Core(TM)2 Duo CPU T9300 @ 2.50GHz
machdep.cpu.family: 6
machdep.cpu.model: 23
machdep.cpu.extmodel: 1
machdep.cpu.extfamily: 0
machdep.cpu.stepping: 6
machdep.cpu.feature_bits: 3219913727 582589
machdep.cpu.extfeature_bits: 537921536 1
machdep.cpu.signature: 67190
machdep.cpu.brand: 0
machdep.cpu.features: FPU VME DE PSE TSC MSR PAE MCE CX8 APIC SEP MTRR
PGE MCA CMOV PAT PSE36 CLFSH DS ACPI MMX FXSR SSE SSE2 SS HTT TM PBE
SSE3 DTES64 MON DSCPL VMX EST TM2 SSSE3 CX16 TPR PDCM SSE4.1
machdep.cpu.extfeatures: SYSCALL XD EM64T LAHF
machdep.cpu.logical_per_package: 2
machdep.cpu.cores_per_package: 2
machdep.cpu.microcode_version: 1551
machdep.cpu.processor_flag: 3
machdep.cpu.mwait.linesize_min: 64
machdep.cpu.mwait.linesize_max: 64
machdep.cpu.mwait.extensions: 3
machdep.cpu.mwait.sub_Cstates: 51520032
machdep.cpu.thermal.sensor: 1
machdep.cpu.thermal.dynamic_acceleration: 0
machdep.cpu.thermal.invariant_APIC_timer: 0
machdep.cpu.thermal.thresholds: 2
machdep.cpu.thermal.ACNT_MCNT: 1
machdep.cpu.thermal.core_power_limits: 0
machdep.cpu.thermal.fine_grain_clock_mod: 0
machdep.cpu.thermal.package_thermal_intr: 0
machdep.cpu.thermal.hardware_feedback: 0
machdep.cpu.thermal.energy_policy: 0
machdep.cpu.arch_perf.version: 2
machdep.cpu.arch_perf.number: 2
machdep.cpu.arch_perf.width: 40
machdep.cpu.arch_perf.events_number: 7
machdep.cpu.arch_perf.events: 0
machdep.cpu.arch_perf.fixed_number: 3
machdep.cpu.arch_perf.fixed_width: 40
machdep.cpu.cache.linesize: 64
machdep.cpu.cache.L2_associativity: 24
machdep.cpu.cache.size: 6144
machdep.cpu.tlb.inst.small: 128
machdep.cpu.tlb.inst.large: 8
machdep.cpu.tlb.data.small: 16
machdep.cpu.tlb.data.small_level1: 256
machdep.cpu.tlb.data.large: 16
machdep.cpu.tlb.data.large_level1: 32
machdep.cpu.address_bits.physical: 36
machdep.cpu.address_bits.virtual: 48
machdep.cpu.core_count: 2
machdep.cpu.thread_count: 2
 
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well it looks like the microcode insertion worked :D which is very interesting given what happens with the XS1,1 and MP1,1/2,1 under the same sort of situation. (gives me some hope for getting E0 CPUs working in the MP3,1)

it seems like the speed reporting issue is somewhere else in the BootROM then.

sadly I dont have an iMac8,1 BootROM dump nor did apple ever put out any firmware updates for the iMac8,1 that we could use :(
 
I have an iMac8,1 stored, if you need a dump.

send it to @beyre83 he is the daring chap with the iMac7,1 :) (though I wouldn't mind a dump my self to play with if your offering :D )

however remember the iMac8,1s Serial number will be in the BootROM so remember to replace that with some other string of the same length :)
 
I have an iMac8,1 stored, if you need a dump.

I would be very much after a 8,1 dump as mentioned it's not available anywhere else
and would save me a small fortune if I had to buy a logic board just to dump the firmware :p
[doublepost=1529737421][/doublepost]also the firmware we are editing is the BootRom right..... isn't the hardware sensors that detect speed etc stored in the SMC Rom which is different to the boot rom....... just a thought

****EDIT****

I downloaded CPU-X

and its interesting to say the least....

NayTb6a.jpg
 
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MacBook Pro 4,1 have a T9300 chip natively as a factory fitted part.....
this get's me thinking about microcodes again if i had the MBP 4,1 Dump
I could play around with extracting the microcodes from it....
 
I would be very much after a 8,1 dump as mentioned it's not available anywhere else
and would save me a small fortune if I had to buy a logic board just to dump the firmware :p

I need to get it out of storage, I'll try to do this tomorrow.
 
So I downloaded a MacBook Pro 4,1 Bios cost me £3 from a polish forum lol (cheaper than buying a MBP 4,1) i compared the two microcodes from the Stock iMac 7,1 & the MBP 4,1 as shown below

B4ZfCFJ.jpg


The iMac 7,1 has one extra field that the MBP 4,1 does not and that's 6FB B0(176) 2007/01/07
so I removed that from the iMac 7,1 Rom and added the 4 MBP 4,1 Microcodes saved it to a different file
rebooted and were still stuck at 400Mhz I am beginning to suspect it's something todo with the multiplier...
and that's what's causing the issue and not the Microcodes....
 
Oh yah do know the 400Mhz thing is purely cosmetic right?

the CPU is still running at full speed, you can run geekbench etc and see that its running perfectly fine :)

it would still be cool to fix it however :)
 
Oh yah do know the 400Mhz thing is purely cosmetic right?

the CPU is still running at full speed, you can run geekbench etc and see that its running perfectly fine :)

it would still be cool to fix it however :)

So I found a 8,1 Mac Rom flashed it..... and no screen no chime but the ****er does turn on as I got FaceTime prompts on my phone and my Mac Pro that a new iMac had signed in....

panic stations hit..... however I took the iMac apart took out the SSD plugged it into my 4,1 booted to that drive turned on screen share.... put ssd back in then connect via the IP address which my router told me the iMac was and......

n2fK3vV.png


Soooooo close to getting it working ya Boiiiii
[doublepost=1529763706][/doublepost]and I was able to get it back to firmware update mode and reflash my stock 7,1 rom back and it chimes and
outputs display like it should :)..... so this gives me a great deal of hope :D
 
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So I found a 8,1 Mac Rom flashed it..... and no screen no chime but the ****er does turn on as I got FaceTime prompts on my phone and my Mac Pro that a new iMac had signed in....

panic stations hit..... however I took the iMac apart took out the SSD plugged it into my 4,1 booted to that drive turned on screen share.... put ssd back in then connect via the IP address which my router told me the iMac was and......

n2fK3vV.png


Soooooo close to getting it working ya Boiiiii

it worked! :) (kinda?)

weird that your display stopped functioning as the GPUs VBIOS is on the GPU it self rather then in the BootROM. have you tried doing a PRAM and SMC reset? also what does Graphics/Displays report? and which Graphics Card does this system have? I know the 2400/2600s got Firmware updates I wonder if yours needs a FW update to work with the iMac8,1 BootROM?

also out of curiosity do you have any 1066Mhz FSB CPUs you can try in the system? the iMac7,1 schematics mention 1066Mhz FSB support, I wonder if the iMac8,1 firmware will actually enable it.
 
it worked! :) (kinda?)

weird that your display stopped functioning as the GPUs VBIOS is on the GPU it self rather then in the BootROM. have you tried doing a PRAM and SMC reset? also what does Graphics/Displays report? and which Graphics Card does this system have? I know the 2400/2600s got Firmware updates I wonder if yours needs a FW update to work with the iMac8,1 BootROM?

also out of curiosity do you have any 1066Mhz FSB CPUs you can try in the system? the iMac7,1 schematics mention 1066Mhz FSB support, I wonder if the iMac8,1 firmware will actually enable it.

No I don't have any of the EXXX chips to try sadly :( I did try a SMC reset by unplugging the power holding the power button for 30 seconds then plugging backin then pressing the power button no dice.....

GPU Info Under 7,1 BIOS


ATI Radeon HD 2600 Pro:

Chipset Model: ATI,RadeonHD2600
Type: GPU
Bus: PCIe
PCIe Lane Width: x16
VRAM (Dynamic, Max): 256 MB
Vendor: AMD (0x1002)
Device ID: 0x9583
Revision ID: 0x0000
ROM Revision: 113-B2250F-219
EFI Driver Version: 01.00.219

Displays:

iMac:

Display Type: LCD
Resolution: 1680 x 1050 (Widescreen Super eXtended Graphics Array Plus)
UI Looks like: 1680 x 1050
Framebuffer Depth: 24-Bit Color (ARGB8888)
Main Display: Yes
Mirror: Off
Online: Yes
Rotation: Supported
Automatically Adjust Brightness: No

ill flash it back to 8,1 and check again I downloaded the 2400/2600 firmware but tells me it's not needed???
 
No I don't have any of the EXXX chips to try sadly :( I did try a SMC reset by unplugging the power holding the power button for 30 seconds then plugging backin then pressing the power button no dice.....

GPU Info Under 7,1 BIOS


ATI Radeon HD 2600 Pro:

Chipset Model: ATI,RadeonHD2600
Type: GPU
Bus: PCIe
PCIe Lane Width: x16
VRAM (Dynamic, Max): 256 MB
Vendor: AMD (0x1002)
Device ID: 0x9583
Revision ID: 0x0000
ROM Revision: 113-B2250F-219
EFI Driver Version: 01.00.219

Displays:

iMac:

Display Type: LCD
Resolution: 1680 x 1050 (Widescreen Super eXtended Graphics Array Plus)
UI Looks like: 1680 x 1050
Framebuffer Depth: 24-Bit Color (ARGB8888)
Main Display: Yes
Mirror: Off
Online: Yes
Rotation: Supported
Automatically Adjust Brightness: No

ill flash it back to 8,1 and check again I downloaded the 2400/2600 firmware but tells me it's not needed???

Did you tried the external display? Maybe the problem it's on the port mappings.
 
sooo under the 8,1 Bios if you don't reset the PRAM you get no bootable device display on the screen and very grainy
reset pram and it boots and screenshare works under display you now get the following

ATI Radeon HD 2600 Pro:

Chipset Model: ATI,RadeonHD2600
Type: GPU
Bus: PCIe
PCIe Lane Width: x16
VRAM (Dynamic, Max):
Vendor: AMD (0x1002)
Device ID: 0x9583
Revision ID: 0x0000
ROM Revision: 113-B2250F-219
EFI Driver Version: 01.00.219
[doublepost=1529765363][/doublepost]Reading the 7,1 Service Manual for Diagnostic LEDS

LED #3

• Indicates that the computer and the video card are communicating. This LED will be ON when the computer is communicating properly with the video card. If LEDs 1 and 2 are ON and you heard the startup sound, but LED 3 is OFF, then the video card might be installedincorrectly or need replacement.

LED #4

• Indicates that the computer and the LCD display panel are communicating. This LED will be ON when the computer is turned on and video signal is being generated. If the LED is ON and there is no image on the LCD display panel, the LCD display panel or inverter might beinstalled incorrectly or need replacement.

Neither Led 3 or 4 are Lit when running the 8,1 firmware.....
[doublepost=1529767301][/doublepost]I flashed the 8,1 again this time with out the Edited Serial that I did in hex edit with my 7,1 and
still no video or chime... but it now reports as iMac 20" Early 2008 so it must get that info from the
serial number...

I guess one will have to try and compare the two hex files and find differences but then your more
likely to get a proper brick and not a semi brick if you fiddle with two much I guess we need to figure
out why the 8,1 efi is not booting the GPU it could be because of the SMC is wrong version??? but
I don't know how to obtain a 8.1 SMC to flash to it either

I have potentially got an E8435 3.06Ghz Cpu on order :) to test a 1066 Mhz CPU
 
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well the Video card is showing up... so the MXM slot works at least...

its just not detecting the built in LCD for some reason, have you tried as @tsialex mentioned an external monitor via the Mini DVI port?

(BTW looking around it looks like there where a bunch of diffrent Firmware updates for the 2600 Pro...)

also do you have any iMac8,1 video cards kicking around you could try?
 
well the Video card is showing up... so the MXM slot works at least...

its just not detecting the built in LCD for some reason, have you tried as @tsialex mentioned an external monitor via the Mini DVI port?

(BTW looking around it looks like there where a bunch of diffrent Firmware updates for the 2600 Pro...)

also do you have any iMac8,1 video cards kicking around you could try?

No Mac 8,1 Video cards,,, I have a feeling it could be Ram Related... as according to every Mac the 8,1 used PC2-6400 (800Mhz) the 7,1 Uses PC2-5400 667Mhz been through my collection of SO-Dimms and I only have 667Mhz but then again that should not interfear with the GPU either.....
[doublepost=1529770611][/doublepost]the Mini DVI -> DVI = no go no display on external monitor port either
[doublepost=1529771618][/doublepost]it't might be possible to have 8GB of ram in the 7,1 hacked to 8,1 as the 8,1 supports 8GB Unofficially from my google searching ill get me a cheep 2GB stick to test with first no point throwing money away if its not going to get me anywhere :p I shall persist with my tinkering

P.S Lightbulb if you wanna drop me a pm, so I could perhaps add you on FB Messenger (were both uk) and then I can use my phone as sometimes when tinkering I might not have the Mac Pro On
 
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I have ordered 2GB PC2-6400 SODimm should be with me Wednesday at the latest this
will confirm or deny my hunch about the system not booting correctly due to potential ram
issue
 
No Mac 8,1 Video cards,,, I have a feeling it could be Ram Related... as according to every Mac the 8,1 used PC2-6400 (800Mhz) the 7,1 Uses PC2-5400 667Mhz been through my collection of SO-Dimms and I only have 667Mhz but then again that should not interfear with the GPU either.....
[doublepost=1529770611][/doublepost]the Mini DVI -> DVI = no go no display on external monitor port either
[doublepost=1529771618][/doublepost]it't might be possible to have 8GB of ram in the 7,1 hacked to 8,1 as the 8,1 supports 8GB Unofficially from my google searching ill get me a cheep 2GB stick to test with first no point throwing money away if its not going to get me anywhere :p I shall persist with my tinkering

P.S Lightbulb if you wanna drop me a pm, so I could perhaps add you on FB Messenger (were both uk) and then I can use my phone as sometimes when tinkering I might not have the Mac Pro On

I doubt its the RAM sadly, im pretty sure the iMac8,1 works fine with DDR2-667 RAM

as for 8GB, sadly 6GB is still the max RAM, @Surrat tried 8GB in his iMac8,1 and while it would POST OS X would never boot up properly.
 
I doubt its the RAM sadly, im pretty sure the iMac8,1 works fine with DDR2-667 RAM

as for 8GB, sadly 6GB is still the max RAM, @Surrat tried 8GB in his iMac8,1 and while it would POST OS X would never boot up properly.

everything ive read point's to the iMac 8,1 uses DDR2-800 an ifixit guide even talked about only using 800 ram
in the machine shall see tho it was only £5 on the 2GB ram nothing in the grand scheme of things especially if it works
 
I've been following this thread off and on. I have a 24" iMac 8,1, and can dump it if someone points me to a how-to.
 
to dump the 8,1 24” you need to visit dosdude1.com then My Software, then other software then download RomTool that will allow dumping and flashing :)

Really after a 8,1 20” Dump too
[doublepost=1529836376][/doublepost]
Did you tried the external display? Maybe the problem it's on the port mappings.

Any chance of that 8,1 20” Dump :)
 
Any chance of that 8,1 20” Dump :)

Had to take out of storage and remove iCloud/BTMM/FMM/etc before doing the dump. Didn't want to share my BTMM/FMM and Wi-Fi credentials saved on the nvram part of the BootROM…

This BootROM dump, version IM81.88Z.00C1.B00.0802091538, came from a MB324LL/A.

Changed the SystemSerialNumber to FFs , so you can use BlankSerializer to set your own serial and replaced LogicBoardSerialNumber with xxs - you will have to change both to have iCloud/iMessage/FaceTime working.
 

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