Dell 4000, P4, 680RAM, WD hardrive 120G 

I have a Centon 512 PC2700 module in one socket. The
other  socket has a DEll generaic 128 RAM. I removed
the 128 module and installed a PNY 512MB PC2700
module. When I turned the pc back on, the system would
boot into windows.

Replacing the PNY stick with the Dell stick made the
system normal agains. Chaning  the Centen stick with
the PNY brought again no Windows action. 

I did MemTest +v1.65, but the test stopped during Test
7.
WallTime 35:03 Cached 10244 Rsvd Mem 168K MemMap
e820-Std Cache on ECC off Test Std Pass 0 Errors 933
ECC    Erros 0

Unexpected Interrupt - Halting
Test: 3 Errors: 1
Test: 4 Errors: 1
Test: 5 Errors: 188
Test: 6 Errors: 653
Test: 7 Errors: 90

I aslo ran the Windows Memory Diagnostic. The test
stopped running on PASS 1 Test 7.

When I rebooted, this message came up: CMOS/GPNV
checksum bad. Rebooting produced a DOS screen that
mention the name of my ATI Rage 128 video card.

Then the screen changes to the listing of the CPU. The
memory starts counting from 100 until the maxium
amount is reached. Then a dark screen comes up with
this message: No Boot Device Detected; System halted.

If you play with the pc when it is counting RAM, a
screen appears:PLEASE SELECT BOOTDEVICE. But there are
no choices. It is blank page.

So what's wrong with my RAM? Shall I return the PNY to
the store?

This is a library computer. So getting answers will be
slow.

Switching the modules back and forth has brought the
pc to the following messages in boot mode.

 

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