I've never tried to run those two particular cards, however a long time ago I tried to run a GVP HC+8 Series II simultaneously with a GVP GeForce 040 accelerator.
If I recall correctly I couldn't get it to boot from a drive connected to the accelerator. Removing the GVP ROM (both devices had a GVP ROM version 4.15 on them) from the accelerator allowed it to boot from a drive connected to the HC, but not the other way around. I tried changing jumpers around (including the autoboot jumpers) without success.
Eventually I gave up and sold the HC on. I thought it was some fundamental incompatiblity between the two GVP cards, but in hindsight I'm thinking it may just have been a defect in that particular HC. Good luck, in any case, with your boards!
