i will try and explain this problem the best i can in the hope that someone has an idea as to what my problem is. the system in not a new build, its been good for nearly 2 years.
To start with, i started having CRC errors while trying to UN-RAR files and system crashes, so i realised i had a hardware problem. i ran a number of diagnostic tests on my hard drives and all came up fine.
i then removed 1 stick of memory and all was well, so out of curiosity, i put that stick back in and removed the other (i have 2). Again, all was well. I have also used brand new sticks and still the same.
So just to recap, my pc only works with 1 stick of memory, it doesnt matter wether its in slot 1 or 2, just wont work with both slots in use.. i have run memtest on all sticks involved (tried 4 now)and all have no faults. ok, now heres another 1, did i mention that i have 3 memory slots, well the 3rd is a no-go, anything in that and it just wont boot.(i dont care bout that tho, i dont use the 3rd.). i have today flashed the bios as a last resort, but to no avail, the problem is still there. i would really appreciate any ideas on this matter before i go out and buy another mobo. thank very much.

SOLTEK SL-75DRV5-C MOBO
AMD XP2000 CPU
2X 512 VDATA DDR 2700
2X 256 MATRIX DDR 2700
200GB SEAGATE H/D
WINDOWS XP PRO WITH SP2
SAPPHIR RADEON 9600

Welcome to the PC Guide Forums!! :D

Well, you have a couple of options.

1) Try manually setting the RAM down to DDR266 speed and see if that works.

2) Most mobo's are under a 3-year warranty. If the third RAM slot doesn't work at all, I'd say you should contact Soltek and get an RMA number!

thanx for your suggestions saphalline,
i have just set the ram speed to 133mhz and put the other stick back in, it boots ok now which it wouldnt before, but unfortunately im back to 'crc' errors and lock ups. so i guess im back to square 1.
i thought my board only had a 1 year warranty so the reciept is long gone and theyre asking for a purchase date.
just 1 thing tho, when you say to change the ram speed down, im presuming its done in the advanced chipset features, dram clock/drive, then dram clock. i changed it from 'by speed' to 133. im not a total nubee, just never had to alter this before.
thanks.

Yep, that's the way to manually change the RAM speed.

1 year, huh? Bummer. :( If you need a replacement mobo (which it sounds like you might) then you can get a really good deal right now. Prices have dropped on all Socket A stuff. This mobo (http://www.newegg.com/Product/Product.asp?Item=N82E16813138236) is only $55 USD, and it uses the NForce2 Ultra 400 chipset which is better than your current KT333A by a long shot! With that chipset, you can use all 3 of your RAM sticks without a problem. Something to think about...

well thanks again, ive just checked my mobo box (which for some reason i kept) and i cant find anything to say how long the warranty is. i think its time to move on, ive just bin looking at the cost of a athlon 64 mobo n cpu. i need to check your forums tho as i dont know enough about the pci-e graphics cards yet. thanks.