newbie: oc'ing with a7n8x & XP 2600 333mhz FSB ?HELP?

this is my first try at overclocking, so any help would be greatly appreciated.

I setup my computer with the following:
* asus a7n8x v2.0 BIOS 1005 (had to flash coz 1002 wouldn't even recognize AMD XP2600)
* AMD XP 2600 333mhx FSB ( i think it's the thoroughbred, not barton, any ways to tell for sure??)
* 256mbX2 pc2100 kingston, k-byte RAM (got em for cheap)
* gf4 mx440 4X AGP 64mb
*100gb wd 7200rpm

I encounter several problems when I try to overclock.

#1
when i set the cpu multiplier from the BIOS to 13.0x (or higher) than 12.5x, the system shows the cpu speed as 853mhz or some other lower speed. however if i set it as 12.0x it shows a speed of 2400+, which seems to be working, so if i go higher in the multiplier it messes up i guess. I don't understand why this is happening, is this because the CPU needs to be unlocked ? do these cpu's come unlocked ( i heard some of them do). if it needs to be unlocked is it very complicated, any suggestion.

#2
when i set the bus speed from 166mhz to higher at 175mhz, the system doesn't even POST, it says "memory error/failure". I have to clear the BIOS and that's a major pain. maybe i have cheap ram, i'm not sure. also when i set the BIOS settings as aggressive, the system doesn't POST either. i even tried increasing the FSB to 177mhz x 2, and keeping the RAM speed to 133mhz, and it doesn't POST either. Is there something i'm doing wrong or do i need to get better RAM.

please help, any suggestions, ideas, links would be kool.
thanks.

- rayasus a7n8x v2.0 BIOS 1005

Its not really my area of expertise but it sounds like your ram is having a problem with the OC, take your ram to a lower speed and see if it'll post..... put ram on higher timings and see if it posts, if this does'nt help, try bringing down the OC...... start off small and work your way up it small parts....

OC

Welcome to the forums!!!

Your ram is probably the problem. Try smaller changes to FSB and keep the timings on normal.

Your CPU is unlocked, but only for multiplyers 12.5 or lower. You could unlock it for high multiplyers, but I wouldn't. If you ever get better ram, you want the low multiplyers.

Another thing- not all Tbreds are that great at OCing. I have 3. Only one of them does 2280, a 2400+. My 2100+ only does 2155, and my 1800+ only does 2101. Your 2600 is at 2083 at default. It may not have much more than 100 - 200 mhz of headroom for overclocking.

You're PC2100 memory is already above spec when running at default FSB of 166. You need a minimum of PC2700 memory when running 166 FSB. If you really want to overclock, get some quality PC3200 or PC3500 ram (Corsiar, Kingston, OCZ, GeIL, etc.) This will also allow to you run aggressive timings in your bios.

Also, what kind of cooling do you have and do you know what your cpu temps are when idle/loaded?

thanks for the replies.
my cpu idle temp is: 40C
cpu loaded temp is: 45C
mobo temp: idle - 32C, loaded - 34C

- for the cpu i'm using the fan that came with the retail processor
- for the mobo chipset i added a fan on top of the heatsink as I noticed it becomes really hot.

however i have a fan blowing air into the CPU from the top of the case and another pulling air out from the left side of the CPU on the case. i could add another one blowing air onto the CPU on the side of the case.
Do these makeshift cooling help any?

I tried some more settings in the BIOS.
* If i take out one of the 256mb modules (the kingston), the pc will POST even at 175mhz FSB, CPU speed = 2190mhz
* however it will boot into winXP and run for a few mins only to crash doing a memory dump. so i'm guessing the RAM can't handle it.
* 170mhz FSB is a bit more stable but still crashes in WinXP, with memory dump.
* so i guess i'm stuck with 166mhz FSB for the time being until the new ram arrives.


will unlcoking the CPU for higher multipliers help much in getting good speeds ?
any more suggestions for overclocking with my rig ?

thanks.

- ray

Yes, your RAM is one of your major bottlenecks.

PC2100 = DDR266 = 133FSB = 2.1GB/s
PC2700 = DDR333 = 166FSB = 2.7GB/s
PC3200 = DDR400 = 200FSB = 3.2GB/s

I would try and find a quality stick of PC3200 or better if you are looking to really get into overclocking. For myself, I bit the bullet and went with a stick of Corsair XMS PC3500 (DDR466) so I would know that my RAM isn't the culprit of any problems I have.

I'm just noticing that your board temps seem very high, while your cpu temps seem normal. My mainboard temps vary between 19C and 24C. Your 32C temps are like 90F. Either the sensor is reading incorrectly, or you need more fresh air circulating through the case. Please tell me your environment isn't always that hot.

Back to your multiplyer/FSB question, I would just wait until the new memory arrives, unless you are just dying to fiddle around while you wait. If so, just do a search for "wire trick" and you will find info on how to unlock the higher multiplyers.

modenaf1 said:

WELCOME TO THE FORUMS!!!!!!!

Click to expand...

Do you head up the official welcoming committee?

Mustanley,

my board temp seems to be like that all the time except when it's freshly booted (it starts off with 24 and works all the way upto 32-34). maybe the temp sensors are screwed up. also in the bios i noticed a funny thing - the fan on cpu was spinning quite fast but the BIOS displayed 0 rpm and the temp kept on rising to 55 (weird??)

spent a few hours and this is wat i learnt:
my kingston pc2100 256mb (16*16mb) RAM seemed to be funky. i took it out and the system booted at 166mhz RAM speed with the k-byte ram (8*32mb) at CL3.0
RAM speed at 175mhz boots ocassionally.

someone was saying that lower multipliers would be important for oc'ing, i don't understand how it could be useful. my cpu's higher multipliers seem to be locked.

thanks.

- ray

rlr37916 said:

however i have a fan blowing air into the CPU from the top of the case and another pulling air out from the left side of the CPU on the case. i could add another one blowing air onto the CPU on the side of the case.
Do these makeshift cooling help any?

Click to expand...

You should move your fans around a little. The one on the top should be an EXHAUST fan and blow air OUT of the case. Heat rises, so the air at the top of your case should get blown on out.

You should then have air coming in from one side of your case, usually the front, then exiting the back. Keep track of your cfm (cubic feet per minute) coming in and going out. Try to get them pretty close and remember your psu fan is an exhaust fan.

The rest of your OC trouble sounds like the others have gave you great advice. Get better memory and you'll be much better off. I would also recommend picking up a better heat sink and fan than the OEM that came with your cpu.

Welcome to the forums.

Wedo

If your board temp starts low and then inches it's way up 10 degrees, then you need to reorganize your case fans, just as Wedo said. Here's a picture to help you visualize. Just make sure your top fan is setup for exhaust.



A side panel fan blowing onto the cpu area would also be beneficial.

For the lower multipliers comment, this probably stems from the following.

Generally, for your best overclock (and system performance) you want to get the highest FSB you can. Then once you have established a high FSB you start working the CPU multipliers in order to gain the greatest benefit.

I'm a believer in high FSB over high CPU Mhz.

For example, take 2 computers running around 2000Mhz (just a nice round number). Assuming all components and hardware are exactly the same (yeah, yeah, I know it'll never happen), except for the FSB and CPU multiplier:

Computer #1: 166 FSB x 12 CPU multiplier

Computer #2: 200 FSB x 10 CPU multiplier

I would take Comp #2 anyday as it should outperform Comp #1.