I recently decided I needed more RAM and bought a 4GB set. I didn't have any free slots on the motherboard, so I pulled all of the old RAM out (I couldn't remember which of the two sets already in there were the lower capacity) and put in the new sticks along with the higher capacity of the old sticks. Boot-up failed. I re-seated the RAM and tried again. Same issue. I tried just the new sticks, with the same problem. So, I thought, the new RAM is bad. I put the old RAM back and booted it up, and had the same problem. At this point I started trying individual sticks in different slots, and all booted successfully until I put something in slot 1, at which point it would fail to boot. It was working fine before I pulled the old RAM out, and before I spring for a new board (and at this point a new CPU and DDR3 ram to go with it, my stuff is old) I wanted to know how likely you all think it is that somehow changing the RAM caused a slot to fail. If it matters the pertinent system info is:
Motherboard: GIGABYTE GA-M57SLI-S4
Old sets: CORSAIR XMS2 1GB (2 x 512MB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)
CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)
New set: CORSAIR XMS2 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)
Processor: AMD Phenom 9850 BLACK EDITION 2.5GHz Socket AM2+ 125W
I suppose it's also worth noting that although the brands are the same, the old RAM is about 4 years older than the new RAM.
Welcome, Newcomer. Changing RAM can sometimes be a pain in the you know what. I would certainly consider making an upgrade of mobo and CPU, but first, to address your concern.
Some mobos are sensitive to how RAM is used. Meaning, if you mix the RAM, you can sometimes cause boot failures. A simple CMOS clearing can often fix this. I recommend you remove the CMOS battery from the mobo for about a minute. Reinsert the battery and try booting with one stick at a time, preferably with a new one.
If the battery trick doesn't help, you can try changing the jumper settings (consult your mobo manual for instructions). Alternatively, you can use your RAM on a different system to test them.
Sorry, I somehow missed the part of your post where you typed "and all booted successfully until I put something in slot 1". Still, clearing CMOS could matter. I would strongly recommend you not mix the RAM either. The best practice is to use identical DIMMs. Also, when occupying all of the DIMM slots on the mobo, increasing the DRAM voltage supplied to the DIMM slots is often necessary to maintain stability.
You have to remember that there are small contacts inside the RAM slot that may have gotten brittle over time. Removing RAM that it's essentially stuck too could have damaged those contacts especially if you weren't careful. If that's the case then the computer won't POST because it's getting unexpected results from that RAM slot. Considering we are this close to Bulldozer it's hard to justify investing too much in an AM2 board especially if you need SLI
Alright, I tried clearing the CMOS and nothing changed. I'll continue fiddling with it just in case, but I'm gonna start looking for parts. I agree, it would be silly to invest anything in AM2, any upgrades at this point will involve new mobo/cpu/ram. Thanks for the help!