3 gigs works fine, 4 gigs = nothing. Asus p5k/epu

[timbowens]

Hi everyone. I built a new computer about 3 weeks ago, here are the specs:

e8400
8800gt
Asus p5k/epu
antec neopower 430
OCZ Platinum 6400
2 hard drives

So I initially put 2 gigs of stated ram in the machine and it works like a charm. Last week I bought an additional two gigs, put them in, and nada. The fans come on, the power light on the tower comes on, but thats it. No video, the monitor doesn't even come out of sleep mode. Also, I suppose I should note, the fans are at top speed, like the BIOS hasn't enacted my fan speed settings.

If I take one stick out (tried both dimms), it works just fine. 3 gigs = fine, 4 gigs = oh noes.

Also, I have my system oc'ed. My ram timings are set to factory recommendations (4-5-4-15) and the volts are set to 2.1
I've also tried loading the default BIOS, and that still didn't work.

I've tried getting help from the Asus forums, but to no avail.

Anyone have any ideas?

 

[Proximon]

It's double sided RAM. They only support SS RAM in all 4 slots... pretty common. Sorry, I do not know if they can be made to work.

 

[calinkula]

I don't see why it wouldn't work. I have 4 sticks of RAM in my P5K SE, essentially the same MB. I would say you have a bad stick of RAM or a bad slot on your MB. You could test this by testing the RAM one by one. Stick one RAM stick into a known working slot, see if your computer will boot and then repeat until you know that all the RAM works. Then take one stick of known working RAM and try it in each slot. *Note: Not having your RAM seated properly will cause problems and you may have to push harder than you think.*

Don't forget about the Memory Remap setting in bios. Enable if you have a 64-bit OS and disable if you run 32-bit.

 

[timbowens]

Well, this is my second kit of ram as i've rma'ed the last kit, so I don't think it is the ram, and I have the memory remap setting enabled so i don't think it is that either.

Also, I've tried individual sticks at once, in all the dimms with no problems.

So annoyed with this board right now...

 

[calinkula]

Wow.... that is annoying. So you've RMA'd the RAM and tried a known working stick in each slot..... hhhmmmmmm... Not sure if it would help or not, but bump the voltage on the RAM up a notch or two. I know my board has a fairly decent droop in voltages, so maybe its causing the RAM to freak out a bit. Is the RAM you have on the QVL?

 

[Proximon]

The only RAM that is approved on the QVL for 4 slots is SS, at least that was all I saw.

 

[calinkula]

I'm lazy so I didn't look up the QVL, but if the board will only support 4 single sided sticks and not 4 double sided sticks you might be out of luck.

 

[timbowens]

Thanks for the input guys, now the only question is do I run 2 gigs or 3. Won't 3 run slower?

 

[calinkula]

If you're running XP then 2GB -> 3GB isn't that great of an increase. Vista still takes as much as you can throw at it.

 

[Proximon]

If you're running XP then 2GB -> 3GB isn't that great of an increase. Vista still takes as much as you can throw at it.

3 Gb can help in some games and memory intensive apps like Photoshop. You lose the dual channel speed increase though, so it depends on what you need to run.

XP and Vista 32-bit are limited to 4Gb of memory addresses, but some of those are used by other hardware. Even if you have 4Gb installed you normally end up with 3 to 3.5GB of available memory.

XP 64 bit and Vista 64 Premium are limited to 16GB, minus the same hardware addresses. Vista Ultimate is 128Gb, although of course no mainstream desktop motherboards support that much.