PCCHIPS M912 rev 1.7

The Serpent Rider wrote:

PCCHIPS M912 rev 1.7

Is there a trick to getting write-back L1 cache working on this board?

There's a good article Give your 486 PC a kick with the AMD 5x86 - 133. I've used it to run the CPU on a mainboard EDOM MV035D. But the BIOS shows wrong CPU speed and I couldn't turn on the WB mode for L1 cache.

Asus VL/I-SV2GX4. However, you require the latest BIOS revision for 5x86 support.
Not sure if it supports WB mode of the CPU.

PCCHIPS M919 rev 3.4

Asus PVI-486SP3. I have revisions 1.22 and 1.8. Haven't built a system yet with the 1.22

feipoa wrote:

The Serpent Rider wrote:

PCCHIPS M912 rev 1.7

Is there a trick to getting write-back L1 cache working on this board?

Actually, I was wondering about this particular motherboard - if anyone has been able to get L1 write-back working on it. Starting with rev 1.7, the BIOS has an option for L1 to be enabled in write-back or write-through mode.

QDI V4P895GRN/SMT V1.1. RedHill calls this board simply QDI OPTi 895.

After a bunch of trial and error this board that worked best for AMD 5x86 at both 133 and 160. It might be not the fastest one, but it sure is stable.

Though, honestly, another option is to just get a DX4-100 chip with WB cache. The drop in performance is not that significant, but it would be a lot easier to find a board for it.

debs3759 wrote:

Asus PVI-486SP3. I have revisions 1.22 and 1.8. Haven't built a system yet with the 1.22

How's the VESA Local Bus performance of this motherboard?

jesolo wrote:

debs3759 wrote:

Asus PVI-486SP3. I have revisions 1.22 and 1.8. Haven't built a system yet with the 1.22

How's the VESA Local Bus performance of this motherboard?

When using the VLB graphics port, the Asus PVI-486SP3 is about 7% slower in Quake compared to its VLB/ISA-only cousin, the Asus VL/I-486SV2GX4. The PVI-486SP3 is only 1% slower in DOOM though.

When using the PCI graphics port, the Asus PVI-486SP3 is about 7% slower in Quake compared to a PCI/ISA-only board of the same chipset (e.g. MSI MS-4141). The PVI-486SP3 is almost 10% slower in DOOM.

So if you're going to use the PVI-486SP3, I recommend using VLB graphics over PCI. For more speed on a socket 3, you'll want to use a PCI/ISA-only or VLB/ISA-only motherboard.

Source: Performance comparison of 486 motherboards with VLB-only, PCI-only, and PCI+VLB

I was wondering about this particular motherboard - if anyone has been able to get L1 write-back working on it.

Can't test mine due to dead voltage regulator and DX4 overdrive in my possession is WT only.

I have an Intel DX4 w/write-back capability. When I set the BIOS to L1:write-back, chkcpu still reports the chip is in write-through mode.