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Re: Sun 450 not working
Posted to Tool & Equipment Forum on 3/14/2017

Hay Jim, Sorry for all of your problems.I know it is very hard to focus when the S%%t hits the fan & the wheels stop turning.I sincerely hope everything straightens out for you.And no problem for unloading.Sometimes we all need to do that & hopefully it made you feel better.Anyway for repairing my Sun-500.I ended up replacing the processor & Slot 1 board.Actually how I found the problem was that not long after I purchased the unit I upgraded the 333 MHz processor with a 433 MHz one & changer the slot 1 board because I just wanted to keep the original one intact so I changed both.After many years of trouble free use the unit would not boot at times.Not even go into the dos power up screen.After E-mailing the builders of the unit,in this case "Granite Micro-systems" to no avail because they never answered me...That really upsets me when a company can't even E-mail you back...I decided to totally disassemble the computer & check everything including the power supply.After finding nothing there I found a web sight that explained how to power up the power supply & check all outputs.That checked OK so problem was in main part or computer.I decided to just reinstall the original 333 processor & board after finding nothing else for the hell of it & wa-la up she went.After that I decided to get another processor & slot 1 board.I actually upgraded the processor to a 633 MHz celeron which worked perfectly.I am now in the process of upgrading the RAM.Just waiting for a couple of new chips.I got the processor from E-bay.Spent $7.00 inc.shipping USED. Worked flawlessly.The slot 1 board from on E-bay for $13.00 new.This was all it took to get the unit up & running again.If you have any more questions about what I did just either E-mail me or call.I will try to help you out as much as I can when you are ready.

Arthur Margotta
Owner/Technician
AJ.'s Ultralights, Automotive & Sport Vehicles
Thompson, Pennsylvania, USA