On Wed 16 Apr 2008 18:01:11 NZST +1200, Steve Holdoway wrote: > I'm trying to get an old Hp system refettled to run for some friends > kids. However, the mobo is running a 600MHz cpu, and I've only got > 64MB of memory for it. I've got a spare mobo with a pentium on it > ( only one, as it's the 24cm square size ), which I want to use. > However, it's a non standard psu, and hasn't got the 4 pin extra power > connector on it. Is it safe to make up a converter to use the spare > disk power supply connector? I've got plenty of old dead psus/disk > power splitters I can rob the fittings from...
Worth a try, but whether it's safe depends on more factors that haven't been mentioned yet. Like whether you make a mistake with getting the pin-outs right... ;) Errors here tend to let the smoke out. You have verified that the 4-pin connector only carries gnd, +5V, +12V? Nothing else is on a drive connector. The idea should work, although it's not totally optimal because of cable lengths and how they run. One potential pitfall I can see is if the PSU has more than one regulator circuit for the +5V, then connecting them together can severely interfere with the regulation and cause the voltage to oscillate, possibly with peaks into dangerous levels (and the electronics won't work with that). PSUs for AMD CPUs with a total power of (guessing) 350-400W and above have that, to keep the +5V current below 20A per regulator. If the total +5V current is below 20A you should be fine. If you wanted to make sure, connect an oscilloscope and turn the power off fast if it shows an epilectic. (The mobo may connect the 4-pin-consector lines with the main connector lines.) My feeling is you should be fine (but I take no liability). Leave the RAM and CPU off and connect it up, turn it on, measure the voltages with a multimeter. > Steve PS yes, all Volker's comments about software engineers and > soldering irons are true in this case, but I reckon even I can manage > this! *vbg* You should be fine. If you weren't, you wouldn't have asked the question as competently. -- Volker Kuhlmann is list0570 with the domain in header http://volker.dnsalias.net/ Please do not CC list postings to me.
