DKB1202 + 68882 higher than 20mhz?

Fingerlickin_B · 19 June 2007, 13:21

Hi folks,

My newly put together A1200 tower has now got a DKB 1202 expansion with the following specs/bits:
8mb RAM (actually more is physically fitted, but can only see 8mb, this is working fine though).
68882 chip fitted.
20mhz crystal is fitted.

So really what I want to know is can I put a faster crystal in it and if so, should I add a heatsink to the FPU?

Amigakit stock 24, 25, 28.6363, 33.330, 50, 60, 64,66, 66.667, 80 & 100mhz crystals...which one to choose?

Any advice would be GREATLY appreciated

PZ.

coze · 19 June 2007, 13:40

just wondering, what do you use the FPU for ?

Fingerlickin_B · 19 June 2007, 14:09

I have no idea, I just put the machine together

Fingerlickin_B · 12 July 2007, 10:10

On a more serious note.

Would people please check this link http://amigakit.leamancomputing.com/...cfcb49ff22227c and tell me which crystals I can use for the following:

a: To speed up the processor of my A600.

b: For my DKB1202 with 68882.

c: To speed up the processor of my A1200.

Someone please let me know, as I don't want to kill anything by over-speeding it

PZ.

coze · 12 July 2007, 10:20

you can't just pop in a faster crystal to a standard amiga and expect it to work. The crystals on amiga boards not only determine processor clock, but also bus, floppy access, video timings.

The DKB1202 may have a seperate crystal which controls only the FPU clock. if this is so you can change it. However, FPU is not something which used a lot, and you won't notice any difference at your computer unless you do some serious 3d rendering or use spreadsheets, database applications.

Fingerlickin_B · 12 July 2007, 10:24

Quote:

Originally Posted by coze

The crystals on amiga boards not only determine processor clock, but also bus, floppy access, video timings.

Ok, thanks man, I was not aware that it would ruin everything else, so I'll avoid changing the mobo crystal

Quote:

Originally Posted by coze

The DKB1202 may have a seperate crystal which controls only the FPU clock. if this is so you can change it. However, FPU is not something which used a lot, and you won't notice any difference at your computer unless you do some serious 3d rendering or use spreadsheets, database applications.

It does, and I appreciate your input, point noted, but could you give me some idea of what I can go up to without causing damage?

Thanks heaps

coze · 12 July 2007, 10:31

I'ld say go for 33 MHz or something if the original is at 20 MHz. It shouldn't cause any damage since the chip is sitting idle, however I can't accept any responsiblity if it blows in your face

Fingerlickin_B · 12 July 2007, 10:33

Cool, many thanks and disclaimer noted!

PZ.

coze · 12 July 2007, 10:42

before you swap the crystal, run your amiga and keep your hand over the chips on the DKB1202 and try to feel how hot they run. Then do the same after swapping the crystal. If any chip is getting too hot to hold your hand on, it's not good. You don't want to burn some GAL or other peculiarity. remember, always be safe

Fingerlickin_B · 12 July 2007, 10:43

Good point man

Fingerlickin_B · 12 November 2007, 08:31

Just a little update and checking some facts...

I went for a 33.330mhz crystal and it's been running fine, without any heating problems.

BUT, the guy I bought it off emailed me today and said the 68882 could handle over 55mhz.

Sounds great to me...can anyone verify?

PZ.

keropi · 12 November 2007, 08:37

why bother overclocking the useless FPU in the amiga? unless u use some ancient rendering prog, there is no point in it...

Fingerlickin_B · 12 November 2007, 09:22

For the sake of it...just like everything else we do with Amigas

PZ.

Zetr0 · 12 November 2007, 12:50

@Fingerz

Cool over-clocking I just love it

you should be able to play the FPU version of doom quite quickly now

The 68882 should handle 50mhz, but remember to put atleast a passive heatsink on it and a small fan if you plan to abuse it

insofar as the A600, I will be working on a VERY cheap CPU/RAM upgrade for it soon. so watch that space.

Fingerlickin_B · 12 November 2007, 12:58

Quote:

Originally Posted by Zetr0

@Fingerz

Cool over-clocking I just love it

you should be able to play the FPU version of doom quite quickly now

The 68882 should handle 50mhz, but remember to put atleast a passive heatsink on it and a small fan if you plan to abuse it

insofar as the A600, I will be working on a VERY cheap CPU/RAM upgrade for it soon. so watch that space.

Always loving the good words from Zetro!

All above noted, new crystal, heatsink, grease, etc ordered this payday!

As for the RAM...I gots to know man, did you fire six shots or only five? (Dirty Harry

) Can you PM me with some info?

Whoot!

PZ.

Zetr0 · 12 November 2007, 13:01

I can indeed, check your PM in a couple moes

Fingerlickin_B · 12 November 2007, 13:06

Incessantly refreshing the PM page as we speak!

PZ.

Zetr0 · 12 November 2007, 13:08

LOL, can you hear me now?!

Fingerlickin_B · 12 November 2007, 13:22

Yeah man, took me while to reply...I can't see the keys properly!

So, I forgot to add in the PM...........I should hold off on an A600 RAM purchase for now?

PZ.

Zetr0 · 12 November 2007, 13:29

@Fingerz

unless you need one in the next couple of months, it might be wise to hold back a bit.

19 June 2007, 13:21	#1
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	DKB1202 + 68882 higher than 20mhz? Hi folks, My newly put together A1200 tower has now got a DKB 1202 expansion with the following specs/bits: 8mb RAM (actually more is physically fitted, but can only see 8mb, this is working fine though). 68882 chip fitted. 20mhz crystal is fitted. So really what I want to know is can I put a faster crystal in it and if so, should I add a heatsink to the FPU? Amigakit stock 24, 25, 28.6363, 33.330, 50, 60, 64,66, 66.667, 80 & 100mhz crystals...which one to choose? Any advice would be GREATLY appreciated PZ.

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19 June 2007, 13:40	#2
coze hastala vista winny vista Join Date: Feb 2006 Location: mt fuji Age: 46 Posts: 1,335	just wondering, what do you use the FPU for ?

19 June 2007, 14:09	#3
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	I have no idea, I just put the machine together

12 July 2007, 10:10	#4
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	On a more serious note. Would people please check this link http://amigakit.leamancomputing.com/...cfcb49ff22227c and tell me which crystals I can use for the following: a: To speed up the processor of my A600. b: For my DKB1202 with 68882. c: To speed up the processor of my A1200. Someone please let me know, as I don't want to kill anything by over-speeding it PZ.

12 July 2007, 10:20	#5
coze hastala vista winny vista Join Date: Feb 2006 Location: mt fuji Age: 46 Posts: 1,335	you can't just pop in a faster crystal to a standard amiga and expect it to work. The crystals on amiga boards not only determine processor clock, but also bus, floppy access, video timings. The DKB1202 may have a seperate crystal which controls only the FPU clock. if this is so you can change it. However, FPU is not something which used a lot, and you won't notice any difference at your computer unless you do some serious 3d rendering or use spreadsheets, database applications.

12 July 2007, 10:31	#7
coze hastala vista winny vista Join Date: Feb 2006 Location: mt fuji Age: 46 Posts: 1,335	I'ld say go for 33 MHz or something if the original is at 20 MHz. It shouldn't cause any damage since the chip is sitting idle, however I can't accept any responsiblity if it blows in your face

12 July 2007, 10:33	#8
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	Cool, many thanks and disclaimer noted! PZ.

12 July 2007, 10:42	#9
coze hastala vista winny vista Join Date: Feb 2006 Location: mt fuji Age: 46 Posts: 1,335	before you swap the crystal, run your amiga and keep your hand over the chips on the DKB1202 and try to feel how hot they run. Then do the same after swapping the crystal. If any chip is getting too hot to hold your hand on, it's not good. You don't want to burn some GAL or other peculiarity. remember, always be safe

12 July 2007, 10:43	#10
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	Good point man

12 November 2007, 08:31	#11
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	Just a little update and checking some facts... I went for a 33.330mhz crystal and it's been running fine, without any heating problems. BUT, the guy I bought it off emailed me today and said the 68882 could handle over 55mhz. Sounds great to me...can anyone verify? PZ.

12 November 2007, 08:37	#12
keropi . Join Date: Oct 2004 Location: Ioannina/Greece Posts: 5,040	why bother overclocking the useless FPU in the amiga? unless u use some ancient rendering prog, there is no point in it...

12 November 2007, 09:22	#13
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	For the sake of it...just like everything else we do with Amigas PZ.

12 November 2007, 12:50	#14
Zetr0 Ya' like it Retr0? Join Date: Jul 2005 Location: United Kingdom Age: 49 Posts: 9,768	@Fingerz Cool over-clocking I just love it you should be able to play the FPU version of doom quite quickly now The 68882 should handle 50mhz, but remember to put atleast a passive heatsink on it and a small fan if you plan to abuse it insofar as the A600, I will be working on a VERY cheap CPU/RAM upgrade for it soon. so watch that space.

12 November 2007, 13:01	#16
Zetr0 Ya' like it Retr0? Join Date: Jul 2005 Location: United Kingdom Age: 49 Posts: 9,768	I can indeed, check your PM in a couple moes

12 November 2007, 13:06	#17
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	Incessantly refreshing the PM page as we speak! PZ.

12 November 2007, 13:08	#18
Zetr0 Ya' like it Retr0? Join Date: Jul 2005 Location: United Kingdom Age: 49 Posts: 9,768	LOL, can you hear me now?!

12 November 2007, 13:22	#19
Fingerlickin_B Amiga Nut Join Date: Oct 2006 Location: Belco, Australia Posts: 2,242	Yeah man, took me while to reply...I can't see the keys properly! So, I forgot to add in the PM...........I should hold off on an A600 RAM purchase for now? PZ.

12 November 2007, 13:29	#20
Zetr0 Ya' like it Retr0? Join Date: Jul 2005 Location: United Kingdom Age: 49 Posts: 9,768	@Fingerz unless you need one in the next couple of months, it might be wise to hold back a bit.

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