If you can't see something like 'Maximum LBA size' or LBA mode in one of the HD setup options then your Motherboard doesn't support LBA.
Adding a new PCI controller card won't help with this, what it will do is allow you to run a fast HD (7200 RPM) on a motherboard that normally only supports 'slower' drives (5400 RPM).
I had the same problem as you on a Pentium 133, I eventually installed a 10gig drive and used the first 8.4 gig. When I upgraded the CPU & Motherboard the new system recognised the full 10gig as the mobo was LBA capable.
So if you want a faster PC you now have a good excuse!, or just buy the smallest drive you can find at a reasonable price - which will probably be a 20gig, and use it as a 8.4 gig drive.
With Win95 you will be struggling to run any modern software so I'd also suggest you upgrade to atleast Win98SE.