Tuesday, 13 June 2017


Myself being a hardware developer, I have always been sceptical about programs like the "Marpet RAM test" software along with the Atari diagnostic cartridge in finding faults.  I always have suspected faults (bad RAM) where no software would ever seem to report such errors.  These errors were basically impossible to track down and bugged me for a long long time.

I made a plea for someone to write a good fast RAM tester program and  Christian Zietz of CHZ-Soft came to the rescue and created YAART aka  "Yet Another Atari RAM Test".

Don't let this innocent sounding name fool you! It is by far the best RAM test software I have used and really gets down to business in tracing faults!  These days I couldn't live without it!

A quote from the website..

"The storage test programs available so far for the ST disrupt that they are usually very simple knitted. Obviously, you will find obvious problems with the RAM, but not subtle errors that occur only after many passages or with certain test patterns. For the PC, there are Memtest86 software, whose test algorithms have been specially optimized to find such errors.

I have now decided to implement some of these algorithms in a test program for the Atari. YAART ( Yet Another Atari RAM Test ) was developed. From the test depth I think it is already better than many other RAM test programs for Atari TOS.

YAART is available in two versions: YAART.TOS is intended exclusively for (mega-) ST (E) computers, but it can also test memory that is already occupied by the operating system or other programs. YAARTTT.TOS, on the other hand, tests only unoccupied memory, but runs on all Atari-compatible computers (eg TT and Falcon) and tests TT-RAM as well as ST-RAM."

I have being using it for some months now and it really does find errors which no other RAM tester program has even been able to find.  It's not often I get excited about such things, but YAART has to be one of the top software essentials to have!  

So HUGE THANKS to Christian for creating this fantastic program!



  1. I used MemTest86 for years, I have had that say there are errors even due to the slot configuration of the dimms sometimes good to have it though, much more useful than a £1000 ram check thing.

    Glad to see such a app for the ST. I had a Amiga one which only tested the memory on the board it came with and did not test the Amigas own internal chip memory or other memory expansions so a bit useless :/

    1. I really like memtest86, it showed RAM errors when no other program would. Then they made memtest87 and changed all the tests and made it totally useless :( I thought I was going mad, 86 would list faults and 87 would never find any.

      So really glad I now have a ST version of memtest86! A serious bit of software which is exxos approved ;)

    2. I had another version Memtest 86+ cant remember why I needed it, it does something different but I cant remember what :p

      Oh I think the text is a dif colour :p

    3. IIRC MT86+ was a fork made by some other devs who were also not particularly pleased at the way MT87 came out... essentially if you wanted a working tester, development had essentially paused at the last release of 86. Oddly enough I think they were officially sanctioned and were given the source by the original team as they weren't really able to or interested in keeping up further progression themselves.

      It really is just a refined version of 86+ with some extra features and updates (e.g. identifying more recent CPUs and memory architectures / speeds, being able to scan larger address ranges etc), without being significantly larger, especially not in terms of the core program (a good thing as that limits the amount of non-relocatable code, and therefore the amount of memory it can't intrinsically test, as well as the likelihood of bad bits actually affecting the program itself). I dunno if they ever figured out a way to have it operate entirely out of CPU cache and thus not have to occupy RAM at all, but I wouldn't be too surprised (generally tests run with it turned off, though, for hopefully obvious reasons).

      Used both, ended up sticking with 86+ as I only have so many spare floppies and usable drives so had to pick one, and it had a few advantages with no real disadvantages. Worked my way though testing the general reliability and maximum reliable speed of a whole bunch of old SIMMs and DIMMs a few years ago, along with the maximum complements (at various speed settings...), compatibility etc with a bunch of spare motherboards. It was quite interesting how some sticks were barely acceptable at their rated speed (and then, in some cases, only when they were the sole module in a system), whilst others could be pushed extremely hard (even when three or four up)... Think I found some PC100s that could go to 150+ MHz... and some PC66s that ideally had to be derated to 60MHz... as well as SIMMs that could have really edgy timings...