alvaro84 wrote:I have only one board with both PCI and VLB slots, an Asus PVI-486SP3. It's a SiS496 one and based on this and other SiS496 boar […]
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amadeus777999 wrote:Speed kings are the late UMC888x and SiS49x based boards, which are PCI only except for boards like the PCChips M919(UMC 888x) which seems to be up to par performance wise.
Users of this board may have more info on the PCI vs VESA performance gap should there exist one.
I have only one board with both PCI and VLB slots, an Asus PVI-486SP3. It's a SiS496 one and based on this and other SiS496 boards I don't even understand the chipset's reputation here. I give it that (pimped up with 1MB of L2 cache) it has nice general speed but when it comes to VGA access it's simply abysmal. Especially compared to UMC888x which is regarded as a fast chipset and ALI M1487/89 which is never mentioned around here. But in 3DBench I could reach the best Am5x86-160 result (103 fps) with an Abit AB-PB4 board and 256kB of 12ns L2 cache. This is about the fastest realistically obtainable (Cx5x86-133 is really a unicorn, as another thread called it lately) 486.
Back to the Asus VIP board, its VLB speed is somewhat faster (like 20-22 MBps in Landmark instead of the 12-15 with PCI cards that give 30+ in the ALI board at 40MHz!) so it's a good match for that system.
In PCPBench VGA speed doesn't dominate this much so a SiS496 with 1MB cache (MS-4144 this time) and slow PCI takes the cake. But I don't know if I have results for the chipsets with the same CPU and same amount of cache. My Shuttle HOT-433 (UMC888x) is equipped with 512k for a bit better performance, just like my
(Note for self: It's time to copy the benchmark files from my DOS7.1 HDD to have exact numbers. And especially Doom benchmarks because that may be more relevant than 3DBench.)
Bottom line: I haven't seen instability or particularly slow performance with my only VIP board (Asus PVI-486SP3) - it's just slow at PCI VGA access because the chipset (SiS496) itself is. And VLB is faster with this specific board - but PCI itself has much more potential with other (UMC, ALI) chipsets because of the faster, more modern cards.
Interesting info. I haven't tinkered with the 486 boards much in recent times but the SiS496 ones always struck me as fast in general and robust in regards to memory, cache and bus speeds.
You're absolutely right that the PCI speed is not up to par to the UMC based board, but due to this it may be better for some outlandish clockspeeds. The LS486Es that I have work at 60/66mhz fsb with Matrox cards at full pci speed. I guess the chipset uses in general "slow" timings for the PCI bus. Not every SiS49x based board is that robust/fast of course. The Zida(49x) board that I had would not allow for the fastest memory timings after 40mhz, no matter which ram stick.
I do not know about this specific version of the Ali chipset but I have to keep an eye out - should I come across one I'll buy it.
Gfx Card: Matrox MilleniumII
Cpu: Am5x86 ADZ@150
==============================
GA-486AM/S@50fsb/PCI(1:1)
DoomSW - 1060 rtics( 70.4fps ) | demo3<fullscreen-2>
DoomRetail - 703 rtics( fps 40.7 ) | demo4<fullscreen>
DoomII - 3069 rtics( fps 50.9 ) | demo3<fullscreen>
3DBench2 - 101.6 fps
Speedsys - VESA 51 MB
Speedsys - L1/L2/MemAvg. - 111 / 77 / 56 MB
Hot433@50fsb/PCI(1:1)
DoomSW - 1060 rtics( 70.4fps ) | demo3<fullscreen-2>
DoomRetail - 701 rtics( fps 40.8 ) | demo4<fullscreen>
DoomII - 3069 rtics( fps 50.9 ) | demo3<fullscreen>
3DBench2 - 101.6 fps
Speedsys - VESA 54 MB
Speedsys - L1/L2/MemAvg. - 110 / 76 / 56 MB
LS486E@50mhz/PCI(1:1)
DoomSW - 1104 rtics( fps 67.6 ) | demo3<fullscreen-2>
DoomRetail - 717 rtics( fps 39.9 ) | demo4<fullscreen>
DoomII - 3209 rtics( fps 48.7 ) | demo3<fullscreen>
3DBench2 - 93.9 fps
Speedsys - VESA 33 MB
Speedsys - L1/L2/MemAvg. - 141 / 69 / 58 MB
Gfx Card: Matrox MilleniumII
Cpu: intelDX4/WB@133mhz
==============================
LS486E@66mhz/PCI(1:1) <2nd level cache disabled>
DoomSW - 1104 rtics( fps 64.8 ) | demo3<fullscreen-2>
DoomRetail - 752 rtics( fps 38.0 ) | demo4<fullscreen>
DoomII - 3350 rtics( fps 46.7 ) | demo3<fullscreen>
3DBench2 - 97.8 fps
Speedsys - VESA 43 MB
Speedsys - L1/L2/MemAvg. - 140 / - / 75 MB
<WriteSpeed of 139.5MB in cachechk>