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scrapcomputing / 486SocketBlaster

A voltage adapter PCB for 486 CPUs
GNU General Public License v2.0
38 stars 5 forks source link

After upgrading my CPU from DX2-66 to 3.3 V DX4 the PC only sees 500MB Disk #9

Open RetroErik opened 1 month ago

RetroErik commented 1 month ago

Last week i upgraded my Compaq 524 CDS from DX2-66 to a AMD 5x86. The machine worked fine, but the PC only sees 500MB of my CF card. Before the CPU upgrade i had a 2 GB Partition,

First i thought it just was a freak event, but today i am upgrading a IBM PS/1 from DX2-66 to a AMD DX4-100 and i have the exact same problem with my CF Card. The CF card is 8GB. Fdisk only sees 528MB, and BIOS the same. There is no option in the BIOS to set other sizes. On the Compaq CDS the BIOS had options to set pother sizes, but it would reset to 500MB on every boot.

Update. I checked the CF card that was on the PS1 before the CPU upgrade it was less than 500MB, so i cannot say for sure its the same issue. Update 2: Does 486SocketBlaster break LBA?

scrapcomputing commented 1 month ago

Interesting... Could you check if all address lines have continuity through the adapter ? If there is a limit at around 500MB, then perhaps some of the address pins some continuity issue? I would check all high-order address bits just in case, or try with a different adapter.

I doubt it would break LBA. All pins are passed through except for the ones for power.