Proliant VRM

[Mike Percival_2]

Just what are the differences in VRM modules for Proliant servers? They all look pretty much the same, but seem to have different part numbers so there must be some differences. I'm sure a Xeon VRM is fundamentally different from a PIII VRM even if they look similar and are physically interchangeable.

I have a Proliant 1600R which originally had a single PII 500Mhz. I put a matched pair of PIII 600's in the system and added an odd VRM I had kicking around, and it worked perfectly and has been for over a year, despite neither of the part numbers matching.

I have just acquired a Proliant ML350 (first generation - SLOT A CPU) motherboard and this has a terminator card but no processors or VRM's fitted. Would the VRM's from the 1600 work in this system? Are the voltages generated different (the 1600 has 100MHz FSB CPU's, the 350 has 133MHz FSB)?

I looked at some stuff from Intel on VRM8.4 and VRM9.0 specs and it seems that these two specs provide different voltages for the same values of the VID pins so I'm wary that even if a CPU generates a certain value for VID4:0, a wrong VRM MAY generate a mismatched voltage and my CPU's go bye-bye.

Also....where can I get info on the original M350 mobo, part number 163357-001. I need jumper and front panel connector info which I can't seem to find anywhere.

Thanks, people!

[Oleg Koroz]

VRM / PPM for ML350 G1
http://partsurfer.hp.com/cgi-bin/spi/showphoto?partnumber=157825-001

For 1600 PIII
http://partsurfer.hp.com/cgi-bin/spi/showphoto?partnumber=329267-001

User Guide
ftp://ftp.compaq.com/pub/supportinformation/techpubs/maintenance_guides/122832-003.pdf
Connectors, Switches, and LED Indicators - Page 134


ML350 (first generation - SLOT 1 CPU)

[Mike Percival_2]

Thanks for the reply but it doesn't actually answer any of my questions!

I know what the two VRM part numbers are, but what are the differences? Is one a drop in replacement for the other - they are after all, visually identical and physically fit.

As for the front panel connectors - what are the actual pin outs for the 12 way front panel connector. I need to hook a power switch, LED's and reset button (if exists) to this mobo but Compaq don't seem to have any detail on this connector. I don't have an ML350 G1 to refer to so the vague Compaq documentation doesn't really help me any!