I can't find this issue anywhere so I hope someone can help:

I have an HP Desktop with 2GB RAM capacity. I have been operating under 1.24GB RAM for some time now & have decided to increase to 2GB. This is where this issue occurred.

My MB has two slots w/ total of 1GB per - DDR 400 PC3200 support, (had 1GB in one slot & 256 in other). I removed the 256 & installed the new 1GB to give it 2 full GB.

But when I powered on my PC almost nothing happened. The fan turned on, the POWER button illuminated but that is it. The monitor did not come out of idle, I cannot hear anything running besides the fan - no Hard drive access, nothing.

To Troubleshoot -->
I first powered down & checked all connections, (especially the monitor), but there were no issues w/ any of the cords and everything was connected properly - I powered on & same issue.

I then tried switching the memory into each other's slots - same issue.
Then, I removed the new RAM thinking I must have purchased a defective unit & the PC booted fine, just like normal BUT-->
Just as a test I tried removing my previous 1GB stick & leaving only the new 1GB stick & powering on...Everything operated normally.

Any ideas?? Thanks to all in advance for your help.

checked to make sure the new ram is the same as the old?

Yes it's the same. I already had a 1GB Kingston stick installed & I bought the exact same stick.

you're saying each dimm has been tried in both slots seperately and works? like the new dimm in each slot and the old dimm in each slot.

model number of hp?

correct, each one works alone in each slot

Pavilion a705w

I know it's a 3-4 yr old economy PC but it should still perform at memory capacity...?

Memory Installed 256 MB
Maximum allowed 1 GB (2 x 512 MB)
Speed supported PC2700 MB/sec (messages at PC2100)
Type 184 pin, DDR1-333 SDRAM
DIMM slots Two

Thanks. I see that on the HP website. Foolishly when I got my first memory stick a couple years ago my friend sent me to CRUCIAL.COM to find out what memory type & speed is needed.
The jerks scanned my computer & said capacity was 2GB - 1GB per DDR slot @ PC3200. I even used Egg's new scan after the stick wouldn't work & it gave the same results.
Plus the stock 256 stick even says PC3200 on it & I've been running at 1.24 for over 2 years.
But I guess it's just a fluke. Thanks for your help & sorry for the time wasted

hey man as long as something is discovered there's no time wasted. good luck.