Not everything.  But there were some very substantial changes between
the original release version of Windows 95 and the OSR2 version, so
much so that I always felt it should have been called Windows 96.

But there are even more differences between Windows 95B and Windows 98
so your assumption is not going to be valid in many cases.

You should look for something that does mention Windows 95B
compatibility, just to be on the safe side.   Because Windows 95 is no
longer supported in any way by Microsoft this means that hardware
manufacturer's can no longer get their drivers tested for Windows 95
compatibility by Microsoft and therefore they are no longer mentioning
this version of Window in their product documentation.

It is possible that some of the newer hardware such as video and/or
sound cards might work with Windows 95B, but you would be taking a
chance.   If you are looking at a specific make and model of video or
sound card then you might want to post a question back here about that
model with Windows 95 and see if anybody is actually using it.

Good luck

Ron Martell     Duncan B.C.    Canada

Only up to a point.

Pre-SR2 Win95 cannot support...
 - FAT32
 - AGP
 - USB
...so anything using those will never work effectively in pre-SR2.

Win95 SR2 has same FAT32 support as Win98/SE/ME, but WinME has a more
capacity-capable FDisk.exe (bug-fixed FDisk available for older 9x).  

Win95 SR2 requires the "USB Suppliment" (USBSUPP.EXE) for AGP and USB
support.  This rebuilds Vmm32.vxd and adds NTKERN.VXD to do this.

Win98 revised USB support, and is now the baseline most driver
software vendors require for current USB devices.

Win98 SE added the WDM (Windows Driver Model) to allow overlap between
Win9x and NT device driver development.  As the consumer base moves
over to NT, I expect Win98 SE to become a common baseline.  

WinME doesn't add much extra value (it has a revised TCP/IP stack that
more closely resembles NT) and is poorly supported by MS at the
industry level (e.g. no WinME resource kit).  So even if WinME is
"still supported" in the same sense Win98 SE is not, I don't expect to
see much "won't work with Win98 SE, will work with WinME" other than
USB removable drives, which enjoy native support in WinME.

When it comes to graphics cards, there are hardware issues to consider
too.  A Win98-era PC with AGP will prolly use AGP 1x or 2x modes,
which in turn use a higher operating voltage than current AGP cards
support.  So you may have to pay more for a slower PCI edition of the
SVGA card you are after - and then find it under-performs because the
processor can't feed it game data fast enough to render at full speed.

Modern sound cards will almost certainly drain processor power too,
given the trend towards "soft" hardware where the processor does the
work via Windows device drivers that may fret about Windows and
DirectX versions.  Bottom line: Don't run new sware on old hware.

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