I just bought a new power supply Corsair CX430 V2 in order to meet the needs of a new graphics card I hope to install. The motherboard is the micro-ATX form factor Asus P5KPL-AM/PS running a Intel C2D E7200 CPU and 2x2GB of DDR2-800 RAM.
Problem: the computer doesn't boot with the new PSU.
The case Power LED turns on alongwith the PSU and CPU fan for about 3-4 seconds before switching off. The comp. works just fine with the current PSU which is a local brand 400W conforming to ATX12V1.3. The new PSU works fine with three other motherboards: two AMD-based ones and one old Gigabyte LGA775 board running a P4 HT chip.
On my motherboard, the following combinations were tried with no success:
1)20+4 pin connector plugged in; each half of the 4+4 ATX 12V connector plugged in, by turn.
2)20 pin connector plugged in; each half of the 4+4 ATX 12V connector plugged in, by turn.
3)20+4 pin connector plugged in; the 4+4 ATX 12V connector not plugged in.
In the above attempts, no other peripherals or add-on cards were present.
With the old PSU, the 20+4 as well as the CPU 4-pin connector is plugged in.
My dealer-engineer is blaming it on motherboard compatibility but that doesn't seem to be the issue.
The motherboard manual on p1-28 says, "we recommend that you use a power supply unit (PSU) that complies with ATX 12 V Specification 2.0 (or later version) and provides a minimum power of 400 W.". The new PSU, as per the manufacturer, "is backward compatible with ATX12V 2.2 and ATX12V 2.01 systems".