>Buck, I tried plugging each from the pair into the>orange/black slot and the second pair of sticks to the second>set of orange/black slots. >>But this time, it wouldn't even post. Noteven if I increase>the voltage on the DIMMS. >>So I had to put it back to the matching pairs. Meaning...The>oragne slots to 1 set of sticks and the black slots to the>second set/pair of sticks.>>Ofcourse it runs when I slow the memory frequency down a lot.>Aquamark benchmarks went down from 173FPS to 160FPS. FSX, I>can't make out the FPS drop that much. Not sure..IF I should>keep the 4Gig or return it.>>BTW..how about if I have a pair of 2Gigs i.e 2 X 2Gigs>utilizing two slots? Would I have to then throttle down the>frequency? I have no intention of going that route. Way too>expensive now. But I am curious.>>MannyManny. Theoretical question right now, but yes, if things work like they did in the past. You were always better off with 2x1gig than with 4x512gig.Different color slots denote different channels.Just put together a nice machine using ASUS's crosshair mobo. The guy ordered the wrong memory, i,e, Corsair XMS2 TwinX 5400 1 gigX2. I told him to get 6400C4. He is using an AMD Athlon 5200. Even with the slower memory it runs pretty quick. The guy is not a simer but he claims the other games he runs see a gigantic improvement over his 939 pin 3400. He got an NVidia 7950 vid card.The crosshair BIOS with it's "Extreme Tweaker" function gives more memory settings you can count, unreal! Some of these newer mobo's with multi power planes may do away with DIMM loading issues.We used a 750 watt SLI rated PSU.

In general, when you go from 2 sticks to 4 sticks, you put more stress on the memory controller. You definitely want to go to a 2T command rate with 4 sticks (looks like your motherboard defaults to this). And you have to relax your latency (5-5-5-18, etc.) and/or speed (266, 333, etc.). First thing is to use very conservative settings to get the 4 sticks to POST. Then go get the latest MemTest here:http://www.memtest.org/Make a bootable MemTest CD. Boot from it and let it run an hour or so. If you see no red, you passed. If you see red, get more conservative with the settings. Then you start bumping up the latency and speed settings, one change, retest with MemTest, another change, another test, etc. When you start getting errors, back it off a bit, run MemTest overnight to be sure its stable, and you're done. You have just figured out how fast your memory can run.Also, 32 bit XP will have trouble using 4 gigs of RAM. There is stuff like PAE and AWE that help, but its not a sure bet. To fully use 4 gigs or more, its best to use a 64 bit OS like 64 bit XP or Vista.

Yeah... I got it to work with the 4 sticks.. but I had to throttle down the frequency. Even then, when I used the /3G switch, it blue screened on my. But I know the memory by itself is ok..Cause I had tested it with just the new 2 sticks.The Aquamark dropped to 160 from 177. Not sure if that is substatial. But this FSX we are talking here. Can't give up even a single FPS. :)Oh well.. I returned it. Lost $40 for restocking fee and shipping. Cost for lessons on memory. ;)2Gigs is ok for WinXP. My concern is Vista. We have no choice to go that route a year from now if we want DX10. Right.Mannythis is what I need,http://www.newegg.com/Product/CustratingRe...N82E16820231112

You'll be ready to buy a whole new computer then Manny ;-)Gary

>You'll be ready to buy a whole new computer then Manny ;-)>>GaryY'know Gary..thats what I thought too.:(Manny