• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

SE w/ Radius accelerator - fitment too tight?


Well-known member
I just swapped my Radius '020 accelerator from one of my SEs into another. The two machines seem to have a different chassis, the one I swapped the board into has a passthrough slot in the chassis like a SE/30, so you can install a vertical card in the PDS slot. The machine I took the board out of does not have that passthrough slot. The edges of the passthrough slot curve down a bit, maybe 1/8 or 1/16 of an inch. When installed, this lip is putting a bit of pressure on one of the ICs on the accelerator, this wasn't a problem in the other machine since that edge wasn't there to touch the chip.

I'm wondering if it is a problem that there is a bit of constant pressure on the board. It's not a lot of pressure, I didn't have to force the analog board into the chassis, but it is definitely touching. I put two layers of electrical tape over the top of the IC just to be safe, but I'm concerned about the long-term effects of having the pressure on the board. The accelerator does have all the original standoffs, so it is mounted firmly to the logic board.

I've attached a couple photos, I've circled the IC causing the issue. In the photo we are looking end-wise at the IC, the chip runs parallel to the back of the machine, I know it's a bit difficult to see what's going on in the photo.

Thoughts? I think the ideal solution would be to either remove some material from the lip, or swap the chassis from the other SE (it's in pretty rough shape, thus the board swap), however if it's ok as-is I'd rather leave it.


  • SE 2.jpg
    SE 2.jpg
    2.2 MB · Views: 13
  • SE 1.jpg
    SE 1.jpg
    2.5 MB · Views: 13


Well-known member
Silly(?) question... why not just swap the chassis between the SEs? It's a faff, but should work.

FWIW, the early SE chassis was indeed "slot-less" - I believe expansions of that period were like your Radius accelerator - mounted horizontally. It was the latter SE chassis where they added the "slot" for vertical cards.


Well-known member
Silly(?) question... why not just swap the chassis between the SEs? It's a faff, but should work.

Really only because it's a bit of a pain to swap the chassis and I don't currently have a very good workspace, but I may end up going that route. I was also thinking of filing that lip a bit. Either way, I did decide against leaving the board installed with the IC touching, I think it would keep me up at night.