Individual Computers - New accelerator cards for A600 & A1200

[mfilos]

@FOL
That means you're moving Indy away from A603 via a custom 48pin connector.
Theoretically it'll work. Dunno how the signal will be after some cm of flat cable to the desired place (I guess under the floppy is the only way possible to fit).

Space is tight...




@amigoun
One more socket fits just fine and keyboard closes np. Be sure to use Sockets with round pins and NOT flat ones as they are taller in height

[gibs]

Wow Jen's, you got a lot of humor

http://cosmosamiga.blogspot.com/2011...rclocking.html

[fitzsteve]

Originally Posted by gibs

Wow Jen's, you got a lot of humor

http://cosmosamiga.blogspot.com/2011...rclocking.html

Poor Cosmos, warranty void - but awesome stuff.

[FOL]

Originally Posted by amigoun

Only putting another sockets under the scandoubler doesnt work here, because it collides with the keyboard and you wont be able to close the cover.

Not what I ment.

@mfilos
Only about 2.5cm to 3cm should be ok.

[gibs]

Just realized that I paid the 30€ upgrade for nothing

Anyway now we know that those cards are the best on the market.
Fastest than the Apollo & Viper.

I like the last pic : http://2.bp.blogspot.com/_ft6jgTxpbj.../ACA630_17.JPG

[amigoun]

@ FOL
I was just writing what I was originally trying.
@ miflos
Yes I know, currently I have one more socket there without any problems.
Anyway I like your A600, especially the PicoPSU solution

[amigoun]

@ gibs
You didnt pay for nothing, you get more power and more ram.

[jimbob]

Whahey! A big box of awesome just arrived for me. I will be testing out the A600 full works from individual computers as soon as I change into some dry underwear.

Thanks Amigakit and especially Jens.

Isn't it odd and a bit great to be able to personally thank the designer of computer parts.

[gibs]

Yeah that's true.

But if I was sure it was possible to overclock I would have kept the 25Mhz...That's a personnal choice but I have no regret : I like my A600 !

[fitzsteve]

Originally Posted by gibs

Yeah that's true.

But if I was sure it was possible to overclock I would have kept the 25Mhz...That's a personnal choice but I have no regret : I like my A600 !

True but we don't know what long term problem there can be from the overclocking, Jens said the Ram was clocked at its full usable speed already.

Unless Cosmos made some other hacks?

I think I a don't try this unless you are L33t warning is in order

Steve.

[Cosmos]

>Unless Cosmos made some other hacks?

No !

The SDRam can handle 133 Mhz !

[alexh]

I thought the warnings were all about thermal implications? It undoubtedly runs hotter.

Originally Posted by Cosmos

The SDRam can handle 133 Mhz !

What about the design programmed into the FPGA/CPLD on the board? Is it timed to 40MHz? Probably not but it seems to be working

[fitzsteve]

This was Jens post:

Originally Posted by Schoenfeld

The divider is in the CPLD, where all the async mainboard interface and the SD-Ram interface is located. Also, it is critical that the SD-Ram controller and the CPU run in sync - a simple clock-doubling for the CPU would not work at all. As I mentioned earlier for the ACA1230, the two cards (28MHz and 56MHz) look the same, but the CPLD contents are substantially different. It's a whole new development.

I really can't help anyone who wants to do weird things to his accelerator. I shouldn't even start to get into this much detail. If you haven't developed an accelerator yourself, you can't do it. I'm not just saying this to protect myself from too much customer support work. I am doing this to protect you from a failure waiting to happen, unless you have at least the same knowledge as Oliver and I have.

Jens

[FOL]

Originally Posted by alexh

I thought the warnings were all about thermal implications? It undoubtedly runs hotter.

Yep,

Its very hot at 25MHz, so pushing it to 42MHz without a lot of extra cooling would be asking for trouble.

[Schoenfeld]

Originally Posted by Cosmos

>Unless Cosmos made some other hacks?

No !

The SDRam can handle 133 Mhz !

Cosmos,

the SD-Ram could only handle such a high frequency if there are enough NOP commands inserted.

The SD-Ram access is:

cycle 1: row-open
cycle 2: column access
cycle 3: NOP (for CL=2)
cycle 4: data take-over and row-close
cycle 5: first possible point for next row-open.

The datasheet clearly states that there must be 20ns space between row-open and column access. The same is true for the time between row-close and the next row-open: This must be 20ns or more.

If you clock faster than 50MHz, then you'd have to do:

1. row-open
2. nop
3. column access
4. nop
5. data take-over & row-close
6. nop
7. first possible point for next row-open.

By overclocking, you are operating the memory out of spec in two critical points. Also, you're moving the phase between memory clock and the command-input. As a result, your computer will not be stable. The CPU might take the overclocking (it's well-cooled), but you're likely to get memory problems.

Jens

[Oliver_A]

Originally Posted by Cosmos

>Unless Cosmos made some other hacks?

No !

The SDRam can handle 133 Mhz !

Yes, but you forget the CPU, speed of CPLD (the logic design is NOT guaranteed to work under 80Mhz) and several timing parameters involved in how we drive the SDRAM, which are violated now because we do a very quick 2-1-1-1 burst. This is only possible because we clock the RAM so slow. If your overclocking works (and you can only tell after running this configuration for several hours under extreme conditions), then it is purely by accident. Take another 68030, CPLD or SDRAM from a different wafer, and this might not work anymore.

For example, some 33Mhz 68030 can take 50Mhz, others fail miserably after a few minutes. This is no way how to design and sell hardware.

We strongly discourage this practice. There is nothing "cool" and innovative about this.

[Cosmos]

All guys said exactly the same words when the 68060 was released in 1995-1996... Don't push more than 50...

I have a Blizzard 1260@80 who works fine since many years now ! Ok, it's a rev6... But written 50 on it...
And without any problems...

[gibs]

Oliver,

Cosmos said the Amiga is stable at 40Mhz.

I'll tell you soon if it's an accident I'm going to the post office to take mine tomorrow.

IC should have made some faster boards

[DDNI]

Originally Posted by gibs

IC should have made some faster boards

lol why??? It's not as if they are having any trouble selling the "sloooow" ones !!

[Cosmos]

Anyways, everyone can think and say what they want...

I keep my lovely 40 Mhz on my beloved ACA630