Am I Lucky Or Is Value Select Just Good?

[hailscott]

Hey i got a 1 gb kit of crosair value select ram and i can get my ram up to 240fsb with HTT@4x 1:1 ratio and timmings of 2.5-3-3-7. is that just luck or just good ram?
http://img143.imageshack.us/img143/2866/mem2407qv.png
http://img62.imageshack.us/img62/827/fsb2453sc.png

[Kougar]

While AMD overclocking is not within my experiences, I believe that is less "luck" and more "DRAM:FSB Ratio" :D

I am not sure how to read a "CPU/11" setting though, but as everyone here uses AMD systems they can answer that. ;) Should be the same principle as Intel's memory divider ratios of 1:1, 3:2, 5:4, etc.

[werty316]

I think you hit a jackpot and got lucky. Most valuse select sticks aren't known for good overclocking memory.

The DRAM:FSB Ratio is just the ratio of the memory compared to the CPU multiplier, sort of. Basically it is a "CPU/11" or 11/11 becuase his CPU uses a "11x" multiplier.

My A64 uses a "9x" multiplier and so if I ran my CPU and memory 1:1 my "DRAM:FSB Ratio" would be "CPU/9" of "9/9".

Lets look at how I have it now:

Basically: its (9/11)*200HTT= 163MHz which is the speed of the memory using a 166MHz(5/6) memory divider.

http://img99.imageshack.us/img99/9647/clipboard016nw1.jpg

More indepth:
CPU is a 3000+ @ 1.8GHz with "9x" cpu mutiplier.
Memory is set to "166MHz" or 5/6 divider in the bios.

So it works like this:
Divisor = CPU Clock Speed / (BIOS Divider * Reference Clock/HTT)
= 1800MHz/ (5/6 * 200)
= 10.8

Memory Clock = CPU Clock Speed / Integer Divisor
= 1800MHz/10.8
= 166

166MHz is what the memory should be set to.

Its easier using the HTT ratio to the 166/133/100 memory dividers.

[Bio-Hazard]

2.5-3-3-7 at 240 HTT for 512 sticks is just about average these days for AMD systems. I have a set of PQI Turbo that will do up to 275 HTT at those same timings.

http://img206.imageshack.us/img206/8462/superpi9lt.jpg

These are the fastest timings I can get with my OCZ 2x512 dual channel kit.
http://img156.imageshack.us/img156/918/ramspeed1ez.jpg

[werty316]

Must be TCCD and BH-5 chips.

I have a Patriot XBLK kit I got upto 275MHz @ 2.5-3-3-7 also; gotta love those TCCD chips ;); too bad there aren't TCCD 2GB kits :(

[Bio-Hazard]

2 gig kits have slightly looser timings, but that's to be expected. Overall performance on a AMD system isn't all that much different between the 1 gig and 2 gig kits when all is said and done though.

2 gig SuperPi times.
http://img296.imageshack.us/img296/6746/superpi2meg6hx.jpg

1 gig SuperPi times.
http://img206.imageshack.us/img206/8462/superpi9lt.jpg

[werty316]

Yeah but going from 2.5-3-3-7 @ 275MHz to 3-4-4-8 @ 275Mhz sucks but isn't noticable when gaming. 2GBs in FEAR and GRAW improved alot. I haven't tried Oblivion and Codemned yet.

[Bio-Hazard]

Must be TCCD and BH-5 chips.

I have a Patriot XBLK kit I got upto 275MHz @ 2.5-3-3-7 also; gotta love those TCCD chips ;); too bad there aren't TCCD 2GB kits :(You're 100% correct...............

I just love those BH-5 sticks for bench marking, but TCCD are pretty good also when setup right.

[Kougar]

Holy... that's just impressive considering what my 865PE chipset is capable of doing with high performance memory. Even thought the 875P chipset was a step up in that department, Intel had better be working on an integrated memory controller on Nathan...

[werty316]

Heres the max I had my 2GB UCCC kit at so far @ 2.65V:

http://img139.imageshack.us/img139/1246/corsair285mhz3448265v1ob.th.jpg (http://img139.imageshack.us/my.php?image=corsair285mhz3448265v1ob.jpg)

Unfortunately I don't have any screen shots of my TCCD kit but no biggie since I don't use them.

[Bio-Hazard]

Boy I wish my 2 gig kit would clock that high, I'd be in heaven...............;)

I still switch out my ram from time to time depending on if I want to do some special benchmarks.

[werty316]

Can you get them anyhigher than 250Mhz using 3-4-4-8 timings? What chips do you OCZ use? I am thinking they use UCCC also.

Sad thing is I have to run them at 2T in order to get them to 230MHz or higher as my crappy Asus board has a 1T bug.

[Bio-Hazard]

I can get them to 3-3-2-8 1T at 250 MHz, but that's it. It doesn't matter how much voltage I give them or what timings I try, nothing works. But I guess they aren't all that bad. As far as I can tell, the OCZ uses Micron IC's.

[hailscott]

well prime failed in a half hour@240, but it was stable @235 for 8 hours. 3d mark 05 ran stable @235 also but not @ 240(failed the cpu tests). but im still happy with that. But i also rarley overclock. i just read the oc forum and try a few things. just to see what it can do on air cooling.

[werty316]

You could alwats use a memory divider if the memory is the battleneck of your OC.

[hailscott]

okay i have a question. Is it okay to overclock my HTT bus from 1000 to 1175 if it runs stable?

http://img445.imageshack.us/img445/3848/everestcpuid2tp.png

[werty316]

Yep having a 1200MHz HT is usually the limit. Even if you have it at lets say 800MHz it won't matter as the latency is low that it doens't affect performance at all.