Cyrix Foundry Agreements

Cyrix extended its wafer supply agreement with SGS-Thomson in 1994 (Originally formed in 1990). Under the new arrangement,
SGS-Thomson increased the number of wafers it produces for Cyrix and is allowed to make a certain
percentage of those same wafers for itself. In addition, Cyrix granted SGS-Thomson the right to use
certain Cyrix-designed chips as part of SGS-Thomson’s ASIC libraries. SGS-Thomson is allowed to
produce and sell such ASIC products under its own name in unlimited quantities, with Cyrix receiving
royalties from the sale of the devices. Also, Cyrix has the right to sell the SGS Thomson-designed ASICs
under its own name.

IBM and Cyrix announced a five-year agreement in (Sept 1993) calling for IBM to manufacture Cyrix's 486, 5x86,
and 6x86 MPUs. The two companies equally share the output of the Cyrix-designed chips. (Terminated in 1998 after The National Buy Out)

Differentiating between Cyrix and IBM Blue Lightning

It is difficult to distinguish IBM Blue Lightning CPU from Cyrix CPU. The behavior of both CPU is very similar to each other. The deference is that IBM Blue Lightning CPU supports MSR but Cyrix 486, 5x86 and 6x86 do not support it. This means that wrmsr instruction cause invalid opcode fault on Cyrix 486, 5x86 and 6x86, but does not on IBM Blue Lightning CPU. To detect invalid opcode by wrmsr, the following handler is prepared:

If we have Cyrix 486, 5x86 or 6x86, the variable trap_by_wrmsr will be change by this handler. Once Cyrix CPU is detected by this method, we will check device ID register to distinguish it.

CYRIX CORPORATION, Plaintiff, v. INTEL CORPORATION, Defendant, v. TEXAS INSTRUMENTS, INC., Intervenor.

NO. 4:92cv52

UNITED STATES DISTRICT COURT FOR THE EASTERN DISTRICT OF TEXAS, SHERMAN DIVISION

846 F. Supp. 522; 1994 U.S. Dist. LEXIS 3477; 32 U.S.P.Q.2D (BNA) 1890

January 21, 1994, Decided

CONCLUSION

Cyrix is entitled to judgment in its favor on its affirmative defenses of patent exhaustion and implied license based on the use or resale of its claim 1 microprocessors purchased from TI and ST.

Signed this day of January, 1994.

UNITED STATES DISTRICT JUDGE

See Also
Cyrix Corp. v. SGS-Thomson Microelectronics, Inc., 77 F3d 1381 (Fed. Cir. 1996).

Cyrix Corporation and SGS-Thomson Microelectronics, Inc. v. Intel Corporation, 803 F. Supp. 1200, 1205-06 (E.D. Tex. 1992),

Cyrix CX486 S Series (TI Produced)	Cyrix DRx2 Clock Doubled 386 Design	Cyrix Cx486DX DX2 and DX2 ST Produced	Ca486DX2 v-XX IBM Made	Cyrix Cx486DX4 Cyrix 5x86 (and ST) IBM Produced
	(these can be on the tops as well)	DX2-50 DX-33 DX 40 DX-2 80GP		DX4-100 5x86 Cyrix AND ST
FFMYWWL			GPFMYWWL	GPFMYWWL
			G IBM P Process   1 3.6V 3 3.45V 4 3.6V F Fab   B Burlington, Vermont C Corbeil France F Fish Kill, NY J ? K Bromont, Quebec M Mask Revision   J   N   Q   S   B   Y Year   4 1994 5 1995 WW Week L Die Lot Code	G IBM P Process   3 486 5 586 0.65u F Fab   F   K   L   M Mask Revision   U   7   8   9   B   Y Year   5 1995 6 1996 WW Week L Die Lot Code

586-120 Samples October 30, production Nov 1995

1990 SGS-Thomson agreement
1995 .35u AT 586/686 5 Layer Phoenix