I have had a similar issue. It appears they are incompatible. I have been looking for MD908 AJ-5-120 MDRAM for my Apocalypse 5D for a while now.
Sadly apparently it only ever surfaces at ridiculous prices so I'll have to keep on looking.

Doornkaat wrote on 2021-06-02, 16:17:

I have had a similar issue. It appears they are incompatible. I have been looking for MD908 AJ-5-120 MDRAM for my Apocalypse 5D for a while now.
Sadly apparently it only ever surfaces at ridiculous prices so I'll have to keep on looking.

Thank you for the confirmation, at what price did you find them?

Apparently there are ET6000 with the 120 installed

Yeah, both of my cards have 120ns.

15€-35€ each not including shipping.
The cheapest ones I found in Germany were ~20€ each.

Doornkaat wrote on 2021-06-02, 16:39:

15€-35€ each not including shipping.
The cheapest ones I found in Germany were ~20€ each.

That's the same price I found €30 for 2 mdram chips.

The Serpent Rider wrote on 2021-06-02, 16:38:

Apparently there are ET6000 with the 120 installed

Yeah, both of my cards have 120ns.

I wonder if there is any difference on memory clock between the 2 versions.

That is reasonable price. specialty chips if limited use, will not be plentiful to find and will have bit of price to go with it. Just buy them.

And yes, there are differences, one are 1MB and other is 1.125MB types, so have to match capacity by matching the part numbers to original: MD908 or MD909 are not same.

MD904, MD906, MD908, MD909, MD910, MD916, MD918 and MD920. These are not same. Match what you have MD9xx to new ones.

https://www.xfree86.org/3.3.6/tseng12.html

Cheers,

pentiumspeed wrote on 2021-06-02, 19:06:

That is reasonable price. specialty chips if limited use, will not be plentiful to find and will have bit of price to go with […]
Show full quote

That is reasonable price. specialty chips if limited use, will not be plentiful to find and will have bit of price to go with it. Just buy them.

And yes, there are differences, one are 1MB and other is 1.125MB types, so have to match capacity by matching the part numbers to original: MD908 or MD909 are not same.

MD904, MD906, MD908, MD909, MD910, MD916, MD918 and MD920. These are not same. Match what you have MD9xx to new ones.

https://www.xfree86.org/3.3.6/tseng12.html

Cheers,

I agree those won't become cheaper as time passes.

That being said the id number is MD908 for both, the differences are the letter and the access time.
Do you know which one is 1mb and which is 1.125?

Thank you.

908 = 1 mb
909 = 1.125 mb

909 chips are rarely used outside of cut-down versions without 4 sockets.

Serpent Rider, curious, if one have pair of MD908 with another pair of empty spots let it be solder pads or sockets upgraded with two more MD908 memory ICs?

Same idea with MD909 upgraded to four chips from two?

Cheers,

Yes, but 909 is absolutely useless in 4 chips configuration. Those additional 0.5 Mb can't be used for anything, especially on ET6000 with poor 135 Mhz RAMDAC.

The Serpent Rider wrote on 2021-06-02, 20:14:

908 = 1 mb
909 = 1.125 mb

909 chips are rarely used outside of cut-down versions without 4 sockets.

The thing is that are both labelled 908, I don't know why this thing 909 came out.
The difference is just on the first letter (AJ vs SJ) and the access time (120 vs 100).
That being said with nssi I noticed that the et6000 is detected as 4mb, while the 6100 is detected as a 2,numbers mb.
If i'm going to buy the right model of mdram do you think they are going to work?

Your is MD908 and stick with this and having 100 with your 120 does not affect the performance as memory clock is fixed in firmware to use 120 and the chip with 100 will be fine at 120. If the other video card has MD909, use MD909.

Where did you get your MD908 with 100 from? I hope this is not from chinese sellers.

Cheers,

I am probably unable to explain myself.
This is my ET6000:

It uses the mdram SJ-5-100, when I check with nssi it detects 4mb of memory.
Then if I socket the mdram chips on the et6100 it still detects 2mb and something memory instead of 4mb.
Since the only difference between the mdram used on the ET6100 and the ET6000 is the AJ vs SJ, I wanted to be sure if i'm going to buy some mdram of the right type it will be detected?
I ask because the layout of the et6100 seems cheaper than the other and before throw away €30 I want to be sure.
I don't understand why people keep mentioning MD908 and MD909, they both use MD908.

I said: your card uses MD908 has to be two more MD908 to upgrade the card from 2.xx MB to 4.xxMB.

Also I said: if you have another card that has MD909 for example, therefore has to be upgraded with two more MD909.

Cannot mix 908 and 909, both are not same.

The timing is set already in the firmware from the start.
The last characters like 100, 120 indicates how long it becomes available on the data lines after address is loaded into chips. If card uses 120, therefore the firmware on it is set up for that timing and if you found chips with 100 to upgrade memory, will work fine still at 120 timing regardless. if card has 100 original, then upgrade 2 more chips with 120, then have issues because the firmware was set for 100 and is too fast for 120.

Cheers,

Cheers,

pentiumspeed wrote on 2021-06-03, 22:19:

I said: your card uses MD908 has to be two more MD908 to upgrade the card from 2.xx MB to 4.xxMB. […]
Show full quote

I said: your card uses MD908 has to be two more MD908 to upgrade the card from 2.xx MB to 4.xxMB.

Also I said: if you have another card that has MD909 for example, therefore has to be upgraded with two more MD909.

Cannot mix 908 and 909, both are not same.

The timing is set already in the firmware from the start.
The last characters like 100, 120 indicates how long it becomes available on the data lines after address is loaded into chips. If card uses 120, therefore the firmware on it is set up for that timing and if you found chips with 100 to upgrade memory, will work fine still at 120 timing regardless. if card has 100 original, then upgrade 2 more chips with 120, then have issues because the firmware was set for 100 and is too fast for 120.

Cheers,

Cheers,

He knows those things.
He is specifically asking wether buying and installing two more MD908 AJ-5-120 chips will make his ET6100 have 4MB of VRAM.
He has tried MD908 SJ-5-120 before and it didn't work. This is why he was wondering if the MD908 SJ-5-120 is incompatible with his card.

Now people are talking about the capacity (MD809 vs. 909) and speed rating (-100 vs. -120) of the chips which he never asked about.

Doornkaat wrote on 2021-06-04, 05:16:

He knows those things. He is specifically asking wether buying and installing two more MD908 AJ-5-120 chips will make his ET6100 […]
Show full quote

He knows those things.
He is specifically asking wether buying and installing two more MD908 AJ-5-120 chips will make his ET6100 have 4MB of VRAM.
He has tried MD908 SJ-5-120 before and it didn't work. This is why he was wondering if the MD908 SJ-5-120 is incompatible with his card.

Now people are talking about the capacity (MD809 vs. 909) and speed rating (-100 vs. -120) of the chips which he never asked about.

Thank you Doornkaat, I hope this will clarify the situation.
We will anyway discover the truth soon since I ordered the mdram chips.

Dunno about AJ & SJ, but in my experience you can mix 908 & 909, but you cannot mix -100 and -120. Even if socketed are faster than soldered ones. I have ET6000 with 908-100, ET6000 with 909-120 and some spare 908-120 MDRAM. 908-100 + 908-120 didn't work, while 909-120 + 908-120 works fine. I'll check if they are AJ or SJ bit later.

Wow that highly unusual. Nemo1985 said his card have 120 soldered, added 2 more of 100 and said didn't work. I was puzzled too.

Next thing, SJ and AJ, I have no answer but from my dram research over the year is usually suffix for internal design that changes over the years or package differences

Cheers,

I just got the AJ-5-120 chips. Now the card is detected as 4mb
So on my hand the mistery is solved, the aj and sj aren't compatible.