TX750W Won't Work in HP e9150t - Why?

Looking for any input on this, drove me nuts for several hours this morning and finally gave up. In summary, installing new Corsair 750W power supply in new HP PC causes PC to fail to POST. I've built several PC's over the years, never hit this type of brick wall.

 

The details:

 

1. We purchased new HP e9150t.

2. The HP PC has been running for several days as burn in, working fine.

3. So that we had enough overhead for larger video card we were looking to swap out the 460W power supply with Corsair CMPSU-750TX 750W power supply. We have this power supply in our current Dell PC, works fine. We just pulled it to install in the new PC.

4. After the Corsair PS is connected to the HP the HP fails to boot. The cooling fan spins up, the power indicators on the PC light up but no other noticable progress - fails to POST.

5. To eliminate any chance of one of the peripherals causing a problem we connected PS to only the 24 and 4 pin connectors on motherboard and booted, no change in response. The attached monitor didn't even acknowledge any signal from PC.

6. To confirm that HP didn't suddenly hit the wall and crap out on us during the PS upgrade we connected the original PS to the HP (only 24 and 4 pin connectors), unit hit POST (monitor registered signal).

7. Connected Corsair back to HP, same non-responsiveness.

8. Connected original HP PS and assembled unit, works fine.

9. Put Corsair back into Dell, Dell works fine.

10. HP just doesn't seem to like the Corsair 750TX power supply

 

So, what I'm trying to understand is why a "better" PS (better wattage) would fail to boot up in the new HP. Any suggestions or anyone have any idea on what may be causing the conflict?

You'd have to ask HP's technical support if the motherboard / PSU design in their computer follows the ATX v2.01 (or higher) specifications.

You'd have to ask HP's technical support if the motherboard / PSU design in their computer follows the ATX v2.01 (or higher) specifications.

I've looked for specs on this motherboard (Pegatron IPMTB-TK), recent design with Core i7 released Jun 2009, so I would expect to follow ATX v2.01 specs.

I wouldn't be so sure about that, i heard Dell tends to use proprietary hardware. Maybe it's the same deal for HP?

I wouldn't be so sure about that, i heard Dell tends to use proprietary hardware. Maybe it's the same deal for HP?

I found in another forum that a user replaced the PSU in their HP Elite with a Corsair 850W - same specs as my 750W, so really doesn't make sense. Dropped him an PM to see if he could share any info on his upgrade.