16GB Installed 12GB Usable

Hey all,

bought some used stuff off a fella on gumtree, very upfront sound bloke, i7 920, gigabyte ex58-ud5 rev 1, 12gb ram and a corsair h50 in a coolermaster 690. gave me the box for the ram and said there was an extra 4 that he couldn't get working.

so i looked it up, said gigabyte board apparently supports triple channel with 4 sticks in this configuration:



i cocked up and put it in the actual slot 1/2/3/5 resulting in 16gb 8gb usable then realised i was an idiot and put it in the proper slots and got 16gb 12 usable. did more searching, problem hunting so here's a quick list of what i've done

• tested all sticks seperately (all working)
• bumped up dram/qpi voltage
• swapped all sticks around in different slots etc
• loosened the heatsink screws since apparently over tightened heatsinks were causing memory problems on x58 boards
• set clock speeds manually
• tried xmp profile
• set clock speeds slightly lower
• reset cmos/overclock to default and tried
• disabled memory limit in msconfig

here's a photo from in the bios showing it recognizes the stick in slot 5 but it's not usable

http://i.imgur.com/jJ1MRCK.jpg

i was on bios version f12 and with the 16gb 12 usable itd boot into windows, once i upgraded it to f13 id get a "detecting dram size" on boot and it'd do that 3 or 4 times and crash before finally booting. took out one stick and put it back in triple channel mode and its working fine. as of now i'm out of ideas, the only thing I found that I couldn't do was to do with memory remapping as I couldn't find anything about that in the bios. any ideas/help/etc would be appreciated

full specs:

i7 920 at stock speeds
gigabyte ga-ex58-ud5 rev1
16gb corsair vengeance ddr3 4x4GB (cmz16gx3m4a1600c9b)
sapphire radeon hd 6850
corsair h50
windows 7 ultimate x64
evga 550w

Have you tried in slots 1,2,3,4 to give dual channel?

try another configuration, it could be a faulty ram slot which is common on such an old x58 board.

also get on ebay and get yourself a cheap xeon x5650 6 core beast.
12gb is still plenty.

Columbo said:

Have you tried in slots 1,2,3,4 to give dual channel?

Click to expand...

Thats what it's currently in right now since I gave up and went to sleep lastnight. Dual channel mode results in 16gb installed 8gb usable and triple results in 16gb installed 12gb usable.

wedrum said:

try another configuration, it could be a faulty ram slot which is common on such an old x58 board.

also get on ebay and get yourself a cheap xeon x5650 6 core beast.
12gb is still plenty.

Click to expand...

I tested each stick/slot individually and they all work, it just feels like there's something blocking the sticks from being enabled or something like that since they come up in the bios but arent in the slot enabled section.

Yeah thats my plan actually, seen some x5650s on there for £50 a pop so im gonna wait until i've done my christmas shopping then grab one.

12gb will be fine for me I don't really do much RAM intensive stuff on a daily basis but the occasional Vegas/AAE/PS project would benefit from it and if I have the stick to use I may aswell give it a shot. I've read of some people fixing it by having to bend a pin or two back into place or even something as simple as reseating the CPU so I'll give that a shot today and if that doesn't work I'll stick with 12GB triple channel.

Cheers fellas.

Reseated the CPU, checked for bent pins or any debris, reinstalled the H50 and no luck. Think I'll just bop the 4gb stick on ebay and try and get a quick £20.

I would say its the motherboard. I had a complete nightmare when building systems with these motherboards. For some reason the X58-UD5 or 7 were VERY VERY finiky with memory. I have even seen systems power off with 24Gb of memory installed to rebood only showing 12/16/20 useable but still showing 24Gb in the BIOS. IIRC We had a nightmare with Corsair XMS but very little issues with Kingston memory I am pretty sure we replaced most Corsair with Kingston.