Hello everyone!
I am restoring an old DEC DECPC LPV+ 425sx,
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and in the process I have several questions about it:
1. Here in the thread above it is stated that you can upgrade the processor by installing an Intel DX2-66, but there is no jumper for the processor multiplier on the board.. For the Intel DX2-66 processor, the BIOS shows a frequency of 33 MHz, not 66 MHz. I used an Intel DX-50, but increasing the bus frequency to 50 MHz can lead to unstable system operation. Is there any way to enable the processor multiplier on this board to use the more stable DX2-66 against the DX-50? The manual does not say anything about upgrading the processor.
2. I can't use CF cards, I tried 128 MB, 512 MB, 1 GB, 2 GB. All cards are automatically detected in the BIOS. But an attempt to run MS-DOS from them leads to a system freeze. When booting from a floppy disk, the CF disk is visible from MS-DOS, files in directories are displayed, but when trying to copy them or start - the system freezes. On my computer, the monitor screen shows version Phoenix 1.02 (there is a 1.0 sticker on the chip). Perhaps it is necessary to update the BIOS? However, it is not clear where the motherboard BIOS itself is? The chip that is installed looks like the video card BIOS, but where is the motherboard BIOS? Or are both BIOSes recorded in this chip - both the motherboard and the video card? Since 3.5 and 5.25 FDDs are installed in the block, I planned to use CF cards for quick information exchange.
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3. The block has 2 factory memory boards 2x4 MB, which is quite small for Win95. The problem with increasing RAM was solved by installing a 32 MB module with parity checking chips, but the computer only sees 16 MB out of 32. The system refuses to accept standard 16 MB modules (without parity checking chips).
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