FS-A1FX video repair

Supporter (7)

14-11-2018, 23:58

I picked up a FX that had a video issue. Upon first boot I was greeted to this screen:

Trying other games, I discovered issues with a few more:

It seems to only be on MSX2 games and not MSX1 titles. I looked over the mobo and did not see any glaring problems. Searching the site for similar issues, a few posts talked about video DRAM going bad. Here is what was installed before I replaced them.

So I went out an got some replacement DRAM, but I could not source 8ns and ended up with 10ns(D41464C). After installing(and adding sockets so if it did not fix it, I could keep trying or put back the old DRAM) it corrected the video issues I had. Just thought I share my experience with the group.

By jepmsx

Champion (281)

15-11-2018, 09:34

Thanks a lot for sharing your experience.
Could you post the picture of the final result? Thus the new sockets that you added would also be seen.
I think that the information would be more completed.
Thanks again!

By Wierzbowsky

Guardian (3648)

15-11-2018, 11:53

Yep, thanks for sharing. Unfortunately we will see more and more failures of the RAM chips in our machines as the years go by...

By SkalTura

Champion (404)

15-11-2018, 15:48

Did you also replace the elco capacitors, these cause all sorts of problems after a few years...

By luppie

Paladin (869)

15-11-2018, 20:13

Have you tried a memory tester, to check the vram?
Could also be a defective VDP

By majors

Supporter (7)

16-11-2018, 15:58

jepmsx wrote:

Could you post the picture of the final result?

Here is a shot of the replacement DRAM installed with sockets.

SkalTura wrote:

Did you also replace the elco capacitors...

No, I did not see the need at this time but I'm well aware of cap failure with my other hobbies.

luppie wrote:

Have you tried a memory tester, to check the vram?
Could also be a defective VDP

I did run testram and it would crash while testing video RAM(further suggesting I had bad DRAM) but after installing the new modules, it passes the test with no errors. I'm glad b/c I feel it would be more of a challenge to source a replacement video chip.

By Nprod

Expert (105)

16-11-2018, 18:45

Good call trying it out with MSX1 games, since those use only 16KB of VRAM you're less likely to run into a bad block of memory.