System issues with both RAM slots filled

[BlehBlehAmiga]

All,

I have an older HP system with an ASUS A7V-VM motherboard; it takes pc133 ram. It came with 512 total, (2x256).

I recently bought 2x512 sticks. ( http://www.newegg.com/Product/Product.asp?Item=N82E16820159006 )

If I put both sticks of RAM in, the system will not boot.

With stick 1 in slot 1, and stick 2 in slot 2, the system gets past the bios flash screen, then hangs with a blank screen.

With stick 2 in slot 1, and stick 1 in slot 2, the system gets to the windows loading screen, flashes a blue screen for a small fraction of a second, and then reboots.

There are two sticks and two slots. I tested all four combinations of 1 stick and 1 slot. Every single one works and the system comes up fine with the 512 MB ram, but no matter what I tried I couldn't get it to work with both sticks.

It also works with one new stick and one old stick (for 768MB).

This is puzzling to me because individually it appears that no stick is busted and no slot is busted, but together they just don't work.

Any thoughts or ideas? (Short of trashing and replacing it, which has already come to mind.)

Thanks

 

[Fraggable]

There may be a max to how much memory the mobo can take, and may be a max to how much each slot can take. Check the mobo's manual of the manufacturer's website to find out.

 

[BadThad]

Without even looking at the modules you bought, I'm willing to bet they are high-density. You should have spent the extra money to buy the low-density modules. The problem you describe is very normal for a SDRAM based system. Toss those two high density modules and buy 2x512MB of some quality (Micron/Crucial) low density RAM and your problem will go away.

 

[RebateMonger]

As mentioned, make sure that the memory modules all meet the motherboard specifications:
-------------------------------------------
Micron's list of compatible memory. Micron's compatible 512MB module is 64x64 PC133.
The label visible on the Newegg product photo says it's also 64x64 PC133 memory
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Next, I'd do individual memory module testing with Mem86+ (or some other memory tester). You prepare a boot CD and run the test for several hours. If all the individual modules pass, then start combining them and see what happens.

I've seen newer motherboards, with Dual Channel options turned on, fail only with COMBINED modules and not with single modules. Dual Channel tends to stress the memory a bit more. But with PC133 RAM, you should be able to combine these modules. Make sure that the order of the modules meets any requirements of the motherboard (occasionally, there are restrictions on which size modules can be used in which slots).