Installed more memory now system is unstable

Take each of the new RAM modules out and see if it boots fine, then try adding one at a time and see if maybe one of them is faulty.

Weird that you have a mobo that supports DDR2-800 and you use 533/675 *shrug*

I took out the sticks and the system runs normally and quickly. I put one of the new sticks in and the post screen showed flex memory and 2GB. Everything went well. a few minutes after i got to the desktop, I was on the internet then I got an error message and it closed. Then none of my games would open.. I took out the stick and put the other one in and same thing. Flex memory wa son post screen and went to desktop. I was able to go onto the internet for a few minutes and then it closed itself. i got an error message then the system restarted without me doing anything.

Before I bought these 2 sticks of ddr2-675, I asked around and everyone said that the ddr2-675 would run in my system but at ddr2-533 speed. My system doesnt support 675 ddr2?
I took out my mobo manual and it says supports 1066/800/533 FSB. and note 1 to use ddr2 800/667 memory module on mobo you must install 800/1066mhz FSB processor. Does my mobo support ddr2-675? I took out the 2 ddr2-675 sticks and no problems, do I have to RMA the new sticks? What should I do?

Some memory modules are stubborn and won't downclock to match your FSB. I would check your sticks out specifically and see if this is the case. Did you also try to pop out your original memory and just use one of the new Corsair DDR2 sticks? That might help clear some things up.

-The String

Yeah try it with JUST the new sticks and see how that works. It might just be a case of two different speed sticks upsetting the mobo. A clock down from 675 to 533 is a pretty big jump. I'm sure if it's just the clock down being the problem, then some BIOS tweaks would most likely solve it. Your mobo definitely supports the sticks no problem.

Make sure when you try just the two corsairs that you do them in dual-channel.

Hope it works out.

Thanx. I'm not home at the moment but I will try that. Take out my original ddr2-533 sticks and just put in the ddr2-675 sticks. One question though, when I do change sticks and it works, how do you tweak the bios to allow all sticks? Do i contact Gigabyte?

*I'll update this reply when I am home later*

I take it that you have your initial 1GB of DDR2-533 modules on "auto detect" settings?

Try going into your BIOS during boot up and set the memory speeds manually to DDR2-533 speeds rather than leaving it on auto detect.

I'm gonna go out on a limb here and say that you can't mix 533MHz RAM with 667MHz RAM, I'm quite sure the BIOS would find this very disturbing and confusing...
I believe you got mixed up here:
If the CPU has a FSB that is higher than the speed of the RAM then the FSB will simply slow down to match the speed of the RAM,
I've never heard of anybody mixing RAM with different speeds in a system, different sizes...yes, different manufacturers...yes

I have mixed lower speed DDR2 memory without a problem. My Dell came with 2 x 256 @ 400 MHz but the MB also supported 533 Mhz. So I first upgraded by adding 2 x 512 @ 533 MHz. All four sticks worked fine together, running at 400 MHz - I did not have to change any settings, just inserted the new memory. Later I purchased 2 x 1 GB and replaced the 2 x 256 @ 400 MHz so now I have 3 GB @ 533.

I havent mixed manufacturers. All 4 sticks are Corsair. Now I checked first before I bought the sticks and everyone has said that yes I can add the ddr2-675 sticks with my 533 sticks....just that the ddr2-675 sticks will be at 533 speed.

do you agree with the other post about taking all my sticks out and just putting the ddr2-675 in? Do I need a bios tweaking or do I change the memory setting in bios screen?

I took out my 2 ddr2-675 sticks and left my original ddr2-533 sticks. Should I change auto-detect before I put in the new sticks? Or should I follow the other guy by removing all the sticks and just put in the ddr20675 sticks

Just install the 2 1gig sticks of 675 ram and see what happens from there.You should be fine though.I do know that higher speed ram does not always like to be defaulted to a slower speed.Besides,2 gigs is plenty for now.Save your other 2 sticks for another build.That's what I always do when I replace a piece of hardware.I keep it till I have another system to build.Goodluck.

Dahak

AMD X2-4400+@2.4 S-939
EVGA NF4 SLI MB
2X EVGA 7800GT IN SLI
2X1GIG DDR IN DC MODE
WD300GIG HD
EXTREME 19IN.MONITOR 1280X1024
ACE 520WATT PSU
COOLERMASTER MINI R120

my giga DQ6 on 2x1gb corsair ddr2 800 and 2x1gb Kingston ddr2 667





50% OC


no problem at all


Intel C2D E6600
Gigabyte 965P DQ6
2x1 corsair ddr 2 800c4
2x1 Kingston value ram ddr2 667
inno3d 780gb0gtx
xfi extreme music
plextor 716sa
hec win power 550watts
ThermalTake Aquarius 2
2 74gb WD raptor raid 0
2 250gb WD2500KS

Hiyaa. Thank you. Ok i took out all the ram. I just put in the ddr2-675 2GB kit in and everything is fine now. the system is back to being stable. Maybe I'll put the other sticks back in but for now Ill leave it at 2GB


Thanx for everyones help  

2 gig is plenty of RAM, even for Vista...

Some day I would like to see a MB with lots of RAM slots that accepts all kinds of memory - so I could take all these old sticks I have accumulated and plug them into one board.

I would venture to say that voltage/timings had something to do with it. Both may require different settings. It's possible that your 2GB was having a conflict with the timings of the 1GB sticks, or the voltage was too low. The board can't change timings for individual channels, so if your 1GB setup was at 4-4-4-12 and your 2GB required 5-5-5-15, then yeah you may have had some conflicts. Check the timings/voltage settings for each type and see if it's different?