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UEFIMaster

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Discussion starter · #1 ·
So AMD released the Golden Rabbit 7900 worldwide and its clearly artificially limited for no reason more than pure GREED (to up sell the 7900xt) and no this is not a conspiracy theory but a fact:


The GDDR6 hynix H56G42AS8DX-014 is actually rated for 20Gbs but in the GRE only works at 18Gbs and that is a 100% firmware restriction like the Steam Deck 5600Mts LPDDR5.

So the most important limitations are power and memory bandwidth and to bypass the power limit i thinck the EVC2 from ElmorLabs should work right?

This way:


Elmor said in that video at 11:10 that all amd cards use the same debug header and connecting the EVC2 to it can be used to lower the current telemetry readings provided by the VRM and that will bypass the power limit.

And the memory bandwidth limit i think it can be bypassed using the MCT from igorsLab but i not sure if it works for the 7000 series GPUs.


Last but not least i know that AMD locked the VBIOS on RDNA 3 gpus but can the VBIOS be modded and then flashed with a external SPI programmer or there are security measures (PSP or SMU?) like the Nvidia FALCON that will make the GPU not working after that?

Of course i don't have the GPU on hand and i asking all this because i really don't want to waste 600€ if AMD is the one deciding what i do with my ****ing property as they have absolutely no right to do that.:mad:
 
Memory can probably go as high as 7800 XTX since they share a lot of similar parts.
 
There's no MCT or MPT support for the Radeon 7000 series, AMD blocked off that.
 
Discussion starter · #6 ·
As you can get RX 6950 XT at the same price and performance, there is no point to buy anything lower than RX 7900 XT.
Well in my country the 6950XT is out of stock everywhere and the lowest price for the RX 7900XT is 800€ so that is at least 200€ more than the 7900GRE and the only real difference between this two are 4CU (80 vs 84) and 4GB of memory (16 vs 20) and to me that is not worth 200€ difference if there is a way to unlock the full performance of the 7900GRE is worth to try.
 
Discussion starter · #8 ·
Memory can probably go as high as 7800 XTX since they share a lot of similar parts.
Both of them use exactly the same 20gbs rated GDDR6 from hynix:



The 7900GRE is just capped to 18gbs in firmware (vbios) just for artificial market segmentation reasons and that is just an evil and dishonest business practice.
 
I was curious just how limited tuning is on these cards and

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Holy crap that's bad. Max allowed mem clock 18.5GT/s effective, max allowed core clock 2803Mhz :-O Lowest I've seen yet for RX 7000 series.
Not much point sticking an EVC on one of these, the clock limits will get ya before voltage limit.

VBIOS editing for 7000 series when?! (yeah I know- never.)
 
I've been really irritated by the reviews, seems like noone has tried to overcome the clock disadvantages of the GRE when the specs on paper alone should net more than a 13% improvement over the 7800xt. Though seems like AMD has really handicapped it. It is bound to have some OC headroom with those anemic clocks, coupled with an increase power envelope (if an AIB will make it happen) and we should see 20% over the 7800xt I would think.
 
The card was originally meant for the Chinese market. The limits placed on the card where there to circumvent certain international restrictions. Not really AMD's fault.
 
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I've been really irritated by the reviews, seems like noone has tried to overcome the clock disadvantages of the GRE when the specs on paper alone should net more than a 13% improvement over the 7800xt. Though seems like AMD has really handicapped it. It is bound to have some OC headroom with those anemic clocks, coupled with an increase power envelope (if an AIB will make it happen) and we should see 20% over the 7800xt I would think.
Well, it has a lot more CU than 7800 XT so the real bottleneck is memory.
 
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I've been really irritated by the reviews, seems like noone has tried to overcome the clock disadvantages of the GRE when the specs on paper alone should net more than a 13% improvement over the 7800xt. Though seems like AMD has really handicapped it. It is bound to have some OC headroom with those anemic clocks, coupled with an increase power envelope (if an AIB will make it happen) and we should see 20% over the 7800xt I would think.
They can't overcome the clock disadvantage because the core clocks are locked at 2803Mhz max. The slider apparently doesn't go any further. And only 2316Mhz/18.53GT/s is allowed for the VRAM :-(

Looking at the TPU Nitro+ 7900GRE review linked a couple posts up, the new AiB models allow over 300W TBP- up to 355W for the Nitro+. And they did basically max out the clocks within what's possible, 2747Mhz on the Nitro and I see they got a Steel Legend GRE up to 2802Mhz which is right at the limit.

The problem here is the limited VRAM/Core clock adjustments allowed by AMD and there's currently no way to get around those on RX 7000-series.

Edit to add- and the 256-bit VRAM bus ofc. Combined with the low mem clocks, the GRE has only ~70% the bandwidth of the 7900XT and even slightly less bandwidth available than the 7800XT.
 
Has anyone tried to see if the 7900XT bios can work on it? I remember back in the day AMD tried to do this with Vegas56, people just flash the Vegas64 bios on it and gained back the GPU and VRAM clocks.
 
They can't overcome the clock disadvantage because the core clocks are locked at 2803Mhz max. The slider apparently doesn't go any further. And only 2316Mhz/18.53GT/s is allowed for the VRAM :-(

Looking at the TPU Nitro+ 7900GRE review linked a couple posts up, the new AiB models allow over 300W TBP- up to 355W for the Nitro+. And they did basically max out the clocks within what's possible, 2747Mhz on the Nitro and I see they got a Steel Legend GRE up to 2802Mhz which is right at the limit.

The problem here is the limited VRAM/Core clock adjustments allowed by AMD and there's currently no way to get around those on RX 7000-series.

Edit to add- and the 256-bit VRAM bus ofc. Combined with the low mem clocks, the GRE has only ~70% the bandwidth of the 7900XT and even slightly less bandwidth available than the 7800XT.
That’s a damn shame. This card should be AMDs crown jewel right now. As far as price/performance.
 
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Has anyone tried to see if the 7900XT bios can work on it? I remember back in the day AMD tried to do this with Vegas56, people just flash the Vegas64 bios on it and gained back the GPU and VRAM clocks.
I don't think that works anymore. I tried flashing my 7900XT with an XTX BIOS (using a hardware programmer) to get around power and voltage limits, but no matter which XTX BIOS I tried the AMD driver threw an error and refused to load and with some XTX BIOS the system wouldn't even boot.

I think 5700->5700XT was the last time crossflashing was possible on AMD because I havent found any reliable info about it being done on 6000-series either.
 
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I don't think that works anymore. I tried flashing my 7900XT with an XTX BIOS (using a hardware programmer) to get around power and voltage limits, but no matter which XTX BIOS I tried the AMD driver threw an error and refused to load and with some XTX BIOS the system wouldn't even boot.

I think 5700->5700XT was the last time crossflashing was possible on AMD because I havent found any reliable info about it being done on 6000-series either.
Oh wow, I guess it's really locked down now.
 
Oh wow, I guess it's really locked down now.
Yeah AMD has very much locked down the VBIOS on RX 6000/7000. There's now checks similar to how NV has locked down their VBIOS, except unlike with NV there's no leaked exploit to bypass the checks.

Afaik the RedBIOSEditor team has straight-up just given up on these cards which says a lot.

Not a huge deal for 7800XT / 7900XT / 7900XTX since AMD has been generous with the frequency ceilings for those and EVC can bypass voltage & power limits, but for other 7000-series cards there's a hard clockspeed cap that may never be bypassed.
 
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That’s a damn shame. This card should be AMDs crown jewel right now. As far as price/performance.
I don't think they have enough GRE to make much a difference really.
 
I was very interested in the GRE as an upgrade path for my Aging Vega 64. But with all this locking down shenanigans I cant really support amd. They used to be enthusiast king but they have locked down the 7000 series so much.

Guess I'm going to keep the Vega kicking and wait and see what Battlemage offers us. At least Arc's can be overclocked. Who knew than Intel would be the last bastion of enthusiast GPU overclocking
 
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