Can a graphics card run on different vram-chips

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I just accidentaly bought a gpu on eBay on which de owner had exchanged the ram-chip without me realizing in the offer.
I dont think that in this case the card will work this way due to poor soldering and probably the wrong chip.
This made me curious though and now im wondering - can a gpu theoretically run on vram from two different manufactures in case the specs and pinout are same?
 
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Anything is possible, but the VBIOS usually has different memory timings if the IC's are different.
 
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Anything is possible, but the VBIOS usually has different memory timings if the IC's are different.
Im not familiar with the pinout of ram chips are they really standardized or is it just allways the same pin-pattern but not every chip has the same configuration?
 
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It's possible to buy 2 graphics cards of the same SKU that have different brands of chips, but the same PCB, so they have to be pin compatible at least some of the time. Other than that, idk, beyond my pay grade.
 

RazorWind

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Im not familiar with the pinout of ram chips are they really standardized or is it just allways the same pin-pattern but not every chip has the same configuration?
Yes, they're standardized. All GDDR5 chips are the same pinout.

Generally speaking, GDDR5 and GDDR6 chips should be interchangeable from one brand to another, with the obvious caveat that the BIOS needs to specify the right timings for the chips you're using. I don't think I'd advise mixing brands or models, but as long as the chips are physically capable of operating with the frequency and timings the card wants to use, it should work.

That said, i'd be seriously impressed if someone managed to replace eight or more large BGA components without making a single mistake. The chances of doing this successfully without commercial grade equipment are pretty slim, IMHO. And, for the record, I've actually attempted this.
 

Ocellaris

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What kind of card is it, was the card sold as working, and why do you think the RAM chip have changed?

I have strong doubts someone “replaced” the RAM chips and then did anything except sell the card as scrap.
 

kirbyrj

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What kind of card is it, was the card sold as working, and why do you think the RAM chip have changed?

I have strong doubts someone “replaced” the RAM chips and then did anything except sell the card as scrap.

The easiest thing to do would be for the OP to post the ebay listing here, but that probably won't happen.
 

philb2

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The easiest thing to do would be for the OP to post the ebay listing here, but that probably won't happen.
Why do you say that? The OP was willing to start this thread. He should know how [H] works.
 

kirbyrj

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Why do you say that? The OP was willing to start this thread. He should know how [H] works.

So we can all look at exactly what he bought vs. his version of the purchase and to answer many of the questions asked by others above such as what kind of card it is and why he thinks the RAM chips were changed.
 

philb2

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So we can all look at exactly what he bought vs. his version of the purchase and to answer many of the questions asked by others above such as what kind of card it is and why he thinks the RAM chips were changed.
What I meant was, why did you say the OP would probably not post the ebay listing?
 

cdabc123

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My German is abit rough but ima say that card is fucked.

You can switch vram chips. You will need a vbios mod to run most. Possible on amd Idk of its as easy on a nvidia card.

Expect to need the proper tools and I still wouldn't say it is a easy job to succeed at.
 
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I don't think so as well. Even though I think I have the right chip liying around but not the re-balling stencil. It also probably won't be wort the time anyway.

But still thanks for the replies
 

RazorWind

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I don't think so as well. Even though I think I have the right chip liying around but not the re-balling stencil. It also probably won't be wort the time anyway.

But still thanks for the replies
Did the seller actually tell you specifically that he replaced a RAM chip on it? What I see in the photos looks more like the flux residue is from an attempt to replace some of the little MLC caps near that bottom ram chip.

Regardless, you can narrow the issue down by just testing each of the power rails for a sane voltage. If you've got greater than zero at every inductor, and the board still doesn't work, chances are, you've got some time with a BGA machine in your future.
 
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The seller didn't specify a replaced memory chip, just that the card might not work but he didn't test it. Therefore I assumed it was just some dirt or a past repair since the arrangement oft the components looked just like it should - that's the reason why I placed my bid. I usually ask the seller beforehand what the problem is in case they don't specify it. Sadly this time he did not respond in time. But in hindsight the two different chips are pretty obvious... :-|
 

kirbyrj

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The seller didn't specify a replaced memory chip, just that the card might not work but he didn't test it. Therefore I assumed it was just some dirt or a past repair since the arrangement oft the components looked just like it should - that's the reason why I placed my bid. I usually ask the seller beforehand what the problem is in case they don't specify it. Sadly this time he did not respond in time. But in hindsight the two different chips are pretty obvious... :-|

Where are you seeing two different chips? I see two (apparently) identical Elpida VRAM chips from the listing. It looks like the back is all corroded from liquid damage or something more than a memory swap.
 
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The seller said the chips aren't identical - but I can say it for sure in a few days anyway. They I'll post the update.
 
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