NexGen Nx586 P90
Am486 DX2/66
Finally I have a running NexGen system! A VLB (Vesa Local Bus) motherboard paired with a Nx586 P90. I paired it up with a generic 16-bit ISA controller card, a 2GB disk loaded with MS-DOS 6.22 and a SPEA V7 Mirage VLB (based on S3 86C805-P). The BIOS settings are default (with most interesting being VLB 0WS) and everything is ready to go.
As I didn't have experience with NexGen before I didn't know what to expect. Of course I knew that Quake wouldn't run due the lack of a FPU but that's about it.
The first thing I noticed was it's tremendous and snappy performance on the DOS-prompt. It loads up really fast (yes, even DOS with it's small footprint has noticeable differences on relatively fast systems) and responds like madness. I quickly loaded up SysCHK and Vidspeed and got a whopping 108389 ASCII chars and 7440 bytes a second! Consider that it runs a VLB card from 1993 
. In comparison; a Pentium 100 using a Stealth 64 PCI does "just" 82471 ASCII chars and using Vidspeed L it outperfoms an Elsa Winner 1000PRO (S3 86C864) on a DX2/66. Not bad! I suspect the 42MHz bus (with VLB clocked accordingly) being the main factor in it's 'snappyness'. I always benchmark with no configuration loaded (CONFIG.SYS with drivers etc.). If you do load EMM386.EXE this snappy-ness is greatly reduced.
However, it's fast performance on the DOS-prompt doesn't tell how fast the system is when running applications. See the benchmarks below which show that the NexGen is in the Pentium 60 or 486DX4/100 range. Keep in mind that NexGen had this setup running in 1994 (when the Pentium 60 and 486DX4/100 were considered high-end and the Pentium 90 for those who wanted the fastest CPU possible) and that NexGen was a new kid on the block regarding PC-processors. Also keep in mind that this CPU doesn't come with a FPU, which got standard with the 486/Pentium but was optional with the 386, so the DOSBench and whetcod benchmarks fall behind and I can't benchmark/run Quake.
Pity that NexGen got out of the game quickly (it was bought by AMD in early 1996), but we can probably thank NexGen for having AMD still around. NexGen was the main factor in AMD's K6 CPU-line and without that the strong running K7 wouldn't have existed.
In the meantime, and years later when I wrote my findings and did the benchmarks, I have built a permanent NexGen Nx586 system with 16MB RAM, ARK1000VLB, 1GB CF-card and an iWill SIDEjr+ controller card. Performance with Doom is 5FPS faster than with the S3 86C805-P which is a nice gain to surpass all the 486-based systems I benchmarked before . Overclocking the P90 to P100 increases the framerate in Doom to 50,67 FPS which is 4 FPS more compared to stock P90.
I've also went through a few PC Games (German version) CD-ROM's from 1995 and so far compatibility is quite good. I recall I wasn't able to run U.S. Navy Fighters. The installation detects a 386 (a 486 is required) but continues the installation and setup. However, the game itself doesn't load. I haven't tested if this might be related to the ARK 1000VL card.
